Heterocyclic compounds, process for their preparation and pharmaceutical compositions containing them and their use in the treatment of diabetes and related diseases

ABSTRACT

The present invention relates to novel antidiabetic compounds, their tautomeric forms, their derivatives, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutically acceptable compositions containing them. This invention particularly relates to novel azolidinedione derivatives of the general formula (I), and their pharmaceutically acceptable salts, pharmaceutically acceptable solvates and pharmaceutical compositions containing them. ##STR1##

FIELD OF THE INVENTION

The present invention relates to novel antidiabetic compounds, their tautomeric forms, their derivatives, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutically acceptable compositions containing them. This invention particularly relates to novel azolidinedione derivatives of the general formula (I), and their pharmaceutically acceptable salts, pharmaceutically acceptable solvates and pharmaceutical compositions containing them. ##STR2##

The present invention also relates to a process for the preparation of the above said novel, azolidinedione derivatives, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, pharmaceutically acceptable solvates, novel intermediates and pharmaceutical compositions containing them.

The azolidinedione derivatives of the general formula (I) defined above of the present invention are useful for the treatment and/or prophylaxis of diseases or conditions in which insulin resistance is the underlying pathophysiological mechanism. Examples of these diseases and conditions are type II diabetes, impaired glucose tolerance, dyslipidaemia, hypertension, coronary heart disease and other cardiovascular disorders including atherosclerosis. The azolidinedione derivatives of the formula (I) are useful for the treatment of insulin resistance associated with obesity and psoriasis. The azolidinedione derivatives of the formula (I) can also be used to treat diabetic complications and can be used for treatment and/or prophylaxis of other diseases and conditions such as polycystic ovarian syndrome (PCOS), certain renal diseases including diabetic nephropathy, glomerulonephritis, glomerular sclerosis, nephrotic syndrome, hypertensive nephrosclerosis, end-stage renal diseases and microalbuminuria as well as certain eating disorders, as aldose reductase inhibitors and for improving cognitive functions in dementia.

BACKGROUND OF THE INVENTION

Insulin resistance is the diminished ability of insulin to exert its biological action across a broad range of concentrations. In insulin resistance, the body secretes abnormally high amounts of insulin to compensate for this defect; failing which, the plasma glucose concentration inevitably rises and develops into diabetes. Among the developed countries, diabetes mellitus is a common problem and is associated with a variety of abnormalities including obesity, hypertension, hyperlipidemia (J. Clin. Invest., (1985) 75: 809-817; N. Engl. J. Med.; (1987) 317: 350-357; J. Clin. Endocrinol. Metab., (1988) 66: 580-583; J. Clin. Invest., (1975) 68: 957-969) and other renal complications (See Patent Application No. WO 95/21608). It is now increasingly being recognized that insulin resistance and relative hyperinsulinemia have a contributory role in obesity, hypertension, atherosclerosis and type 2 diabetes mellitus. The association of insulin resistance with obesity, hypertension and angina has been described as a syndrome having insulin resistance as the central pathogenic link-Syndrome-X. In addition, polycystic ovarian syndrome (Patent Application No. WO 95/07697), psoriasis (Patent Application No. WO 95/35108), dementia (Behavioral Brain Research (1996) 75: 1-11) etc., may also have insulin resistance as a central pathogenic feature.

A number of molecular defects have been associated with insulin resistance. These include reduced expression of insulin receptors on the plasma membrane of insulin responsive cells and alterations in the signal transduction pathways that become activated after insulin binds to its receptor including glucose transport and glycogen synthesis.

Since defective insulin action is thought to be more important than failure of insulin secretion in the development of non-insulin dependent diabetes mellitus and other related complications, this raises doubts about the intrinsic suitability of antidiabetic treatment that is based entirely upon stimulation of insulin release. Recently, Takeda has developed a new class of compounds which are the derivatives of 5-(4-alkoxybenzyl)-2,4-thiazolidinediones of the formula (II) (Ref. Chem. Pharm. Bull. 1982, 30, 3580-3600). In the formula (II), V represents substituted or unsubstituted divalent aromatic group and U represents various groups which have been reported in various patent documents. ##STR3##

By way of examples, U may represent the following groups:

(i) a group of the formula (IIa) where R¹ is hydrogen or hydrocarbon residue or heterocyclic residue which may each be substituted, R² is hydrogen or a lower alkyl which may be substituted by hydroxy group, X is an oxygen or sulphur atom, Z is a hydroxylated methylene or a carbonyl, m is 0 or 1, n is an integer of 1-3. These compounds have been disclosed in the European Patent Application No. 0 177 353 ##STR4##

An example of these compounds is shown in formula (IIb) ##STR5## (ii) a group of the formula (IIc) wherein R¹ and R² are the same or different and each represents hydrogen or C₁ -C₅ alkyl, R³ represents hydrogen, acyl group, a (C₁ -C₆)alkoxycarbonyl group or aralkyloxycarbonyl group, R⁴ -R⁵ are same or different and each represent hydrogen, C₁ -C₅ alkyl or C₁ -C₅ alkoxy or R⁴, R⁵ together represent C₁ -C₄ alkenedioxy group, n is 1, 2, or 3, W represents CH₂, CO, CHOR⁶ group in which R⁶ represents any one of the items or groups defined for R³ and may be the same or different from R³. These compounds are disclosed in the European Patent Application No. 0 139 421. ##STR6##

An example of these compounds is shown in (IId) ##STR7## iii) A group of formula (IIe) where A¹ represents substituted or unsubstituted aromatic heterocyclic group, R¹ represents a hydrogen atom, alkyl group, acyl group, an aralkyl group wherein the aryl moiety may be substituted or unsubstituted, or a substituted or unsubstituted aryl group, n represents an integer in the range from 2 to 6. These compounds are disclosed in European Patent No. 0 306 228. ##STR8##

An example of this compound is shown in formula (IIf) ##STR9## iv) A group of formula (IIg) where Y represents N or CR⁵, R¹, R², R³, R⁴ and R⁵ represents hydrogen, halogen, alkyl and the like and R⁶ represents hydrogen, alkyl, aryl and the like, n represents an integer of 0 to 3. These compounds are disclosed in European Patent Application No. 0 604 983. ##STR10##

An example of this compound is shown in formula (IIh) ##STR11##

Still another class of antihyperglycemic agents are 5-substituted oxazolidine-2,4-diones and 2-substituted-1,2,4-oxadiazolidine-3,5-diones which can be represented in the formula (IIi), ##STR12## where V represents substituted or unsubstituted divalent aryl or hetero aryl group, W represents various groups which have been reported in various patent documents, A represents nitrogen atom or a CH group and B is an oxygen atom.

By way of examples, W may represent the following groups:

v) a group of formula (IIj), where R is (C₁ -C₆)alkyl groups, cycloalkyl group, furyl, thienyl, substituted or unsubstituted phenyl group, X is hydrogen, methyl, methoxy, chloro or fluoro. These compounds have been disclosed in the U.S. Pat. No. 5 037 842. ##STR13##

An example of these compounds is shown in formula (IIk). ##STR14## (vi) A group of formula (III) wherein A¹ represents a substituted or unsubstituted aromatic heterocyclyl group; R¹ represents a hydrogen atom, an alkyl group, an acyl group, an aralkyl group, wherein the aryl moiety may be substituted or unsubstituted or a substituted or unsubstituted aryl group, n represents an integer in the range of from 2 to 6. These compounds, have been disclosed in the patent application No. WO 92/02520. ##STR15##

An example of these compounds is shown in formula (IIm). ##STR16## (vii) A group of formulae (IIn) and (IIo), where R¹ is hydrogen, (C₁ -C₈)alkyl, (C₁ -C₈)alkoxy, trifluoroalkoxy, halogen or trifluoromethyl group, R² is hydrogen or methyl and X is oxygen or sulfur. These compounds have been described in U.S. Pat. No. 5,480,486. ##STR17##

An example of these compounds is shown in formula (IIp) ##STR18##

Some of the above referenced hitherto known antidiabetic compounds seem to possess bone marrow depression, liver and cardiac toxicities and modest potency and consequently, their regular use for the treatment and control of diabetes is becoming limited and restricted.

SUMMARY OF THE INVENTION

With an objective of developing new compounds for the treatment of type II diabetes non-insulin-dependent-diabetes mellitus (NIDDM)! which could be more potent at relatively lower doses and having better efficacy with lower toxicity, we focused our research efforts in a direction of incorporating safety and to have better efficacy, which has resulted in the development of novel azolidinedione derivatives having the general formula (I) as defined above.

The main objective of the present invention is therefore, to provide novel azolidinedione derivatives, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutical compositions containing them, or their mixtures.

Another objective of the present invention is to provide novel azolidinedione derivatives, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutical compositions containing them or their mixtures having enhanced activities, no toxic effect or reduced toxic effect.

Yet another objective of the present invention is to produce a process for the preparation of novel azolidinediones of the formula (I) as defined above, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts and their pharmaceutically acceptable solvates.

Still another objective of the present invention is to provide pharmaceutical compositions containing compounds of the general formula (I), their tautomers, their stereoisomers, their polymorphs, their salts, solvates or their mixtures in combination with suitable carriers, solvents, diluents and other media normally employed in preparing such compositions.

Yet another objective of the present invention is to provide a process for the preparation of the novel intermediate of the formula (III) ##STR19## where G represents --CHO, --NO₂, --NH₂, --CH═NHOH, --CH₂ NHOH, --CH₂ N(OH)CONH₂ or, --CH₂ CH(J)--COOR, where J represents hydroxy group, halogen atom such as chlorine, bromine or iodine and R represents H or lower alkyl group such as methyl, ethyl, or propyl X, Y, Z, R¹, R², R³, n, and Ar are defined as in formula (I).

DETAILED DESCRIPTION OF THE INVENTION

Azolidinedione derivatives of the present invention have the general formula (I) ##STR20##

In the above formula (I), one of X, Y or Z represents C═O or C═S and the remaining of X, Y and Z represent a group C═ or C═C; R¹, R² and R³ are groups either on X, Y or Z or on a nitrogen atom. R¹, R² and R³ may be same or different and represent hydrogen, halogen, hydroxy, or nitro, or optionally substituted groups selected from alkyl, cycloalkyl, alkoxy, cycloalkoxy, aryl, aralkyl, heterocyclyl, heteroaryl, heteroaralkyl, acyl, acyloxy, hydroxyalkyl, amino, acylamino, arylamino, aminoalkyl, aryloxy, alkoxycarbonyl, alkylamino, alkoxyalkyl, alkylthio, thioalkyl groups, carboxylic acid or its derivatives, or sulfonic acid or its derivatives with the provision that when R¹, R² or R³ is on a nitrogen atom it does not represent hydrogen, halogen, hydroxy, nitro, or substituted or unsubstituted aryloxy, alkoxy, cycloalkoxy, acyloxy, alkylthio or carboxylic acid or sulfonic acid groups; or any two of R¹, R² and R³ along with the adjacent atoms to which they are attached may also form a substituted or unsubstituted cyclic structure of from 4 to 7 atoms with one or more double bonds, the cyclic structure may be carbocyclic or may contain one or more heteroatoms selected from oxygen, nitrogen and sulfur. When the groups representing R¹, R² or R³ are substituted, the substituents are selected from the same groups that may represent R¹, R², and R³ such as hydroxy, halogen, or nitro, or optionally substituted groups selected from alkyl, cycloalkyl, alkoxy, cycloalkoxy, aryl, aralkyl, heterocyclyl, heteroaryl, heteroaralkyl, acyl, acyloxy, hydroxyalkyl, amino, acylamino, arylamino, aminoalkyl, aryloxy, alkoxycarbonyl, alkylamino, alkoxyalkyl, alkylthio, thioalkyl groups, carboxylic acid or its derivatives, or sulfonic acid or its derivatives. The linking group represented by --(CH₂)_(n) --O-- in formula (I) may be attached either through nitrogen atom or through X, Y or Z where n is an integer ranging from 1-4. Ar represents an optionally substituted divalent aromatic or heterocyclic group, R⁴ represents hydrogen atom, halogen or lower alkyl group or forms a bond together with the adjacent group A. A represents a nitrogen atom or a group CR⁵ where R⁵ represents hydrogen, halogen or lower alkyl group such as methyl, ethyl, propyl or the like or R⁵ forms a bond together with R⁴ ; B represents an oxygen atom or a sulfur atom when A is CR⁵ and B represents an oxygen atom when A is a nitrogen atom.

Suitable combinations of X, Y and Z that form the ring structure containing X, Y and Z in the formula (I) are represented in the following Table:

    ______________________________________     S. No.   X           Y           Z     ______________________________________     1.       C═O or C═S                          ═C      C═C     2.       C═O or C═S                          C═C     ═C     3.       ═C      C═O or C═S                                      C═C     4.       ═C      C═C     C═O or C═S     5.       C═C     C═O or C═S                                      ═C     6.       C═C     ═C      C═O or C═S     ______________________________________

It is preferred that at least one of X, Y or Z be C═C.

It is preferred that one of X or Y be C═O. Suitable ring structures containing X, Y and Z include ##STR21##

A preferred ring structure is ##STR22##

When R¹, R² and R³ groups are attached to X, Y, and Z it is preferred that R¹, R², and R³ are selected from hydrogen, halogen atom such as fluorine, chlorine, bromine, or iodine; hydroxy, nitro; substituted or unsubstituted (C₁ -C₁₂)alkyl group, especially, linear or branched (C₁ -C₆)alkyl group, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl and the like; cycloalkyl group such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like; cycloalkyloxy group such as cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy and, the like; aryl group such as phenyl or naphthyl, the aryl group may be substituted; aralkyl such as benzyl or phenethyl, the aralkyl group may be substituted; heteroaryl group such as pyridyl, thienyl, furyl, pyrrolyl, oxazolyl, thiazolyl, oxadiazolyl, tetrazolyl, benzopyranyl, benzofuranyl and the like, the heteroaryl group may be substituted; heterocyclyl groups such as aziridinyl, pyrrolidinyl, morpholinyl, piperidinyl and the like, the heterocyclyl group may be substituted; aryloxy such as phenoxy, naphthyloxy, the aryloxy group may be substituted; alkoxycarbonyl such as methoxycarbonyl or ethoxycarbonyl; aryloxycarbonyl group such as optionally substituted phenoxycarbonyl; arylamino group such as HNC₆ H₅ ; amino group; amino(C₁ -C₆)alkyl; hydroxy(C₁ -C₆)alkyl; (C₁ -C₆)alkoxy; thio(C₁ -C₆)alkyl; (C₁ -C₆)alkylthio; acyl group such as acetyl, propionyl or benzoyl, the acyl group may be substituted; acylamino groups such as NHCOCH₃, NHCOC₂ H₅, NHCOC₃ H₇, NHCOC₆ H₅, NHCOOCH₂ C₆ H₅, NHCOOC₂ H₅, NHCOOCH₃ and the like; carboxylic acid or its derivatives such as amides, like CONH₂, CONHMe, CONMe₂, CONHEt, CONEt₂, CONHPh and the like, the carboxylic acid derivatives may be substituted; acyloxy group such as OCOMe, OCOEt, OCOPh and the like which may optionally be substituted; sulfonic acid or its derivatives such as SO₂ NH₂, SO₂ NHMe, SO₂ NMe₂, SO₂ NHCF₃ and the like; the sulfonic acid derivatives may be substituted.

All of the preferred groups that may represent R¹, R² and R³ may be substituted or unsubstituted.

When R¹, R² or R³ are attached to nitrogen atom, it is preferred that R¹, R² and R³ are selected from (C₁ -C₁₂)alkyl group, especially linear or branched (C₁ -C₆)alkyl group, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl groups and the like; cycloalkyl group such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like; aryl group such as phenyl or naphthyl; aralkyl such as benzyl or phenethyl; heteroaryl group such as pyridyl, thienyl, furyl, pyrrolyl, oxazolyl, thiazolyl, oxadiazolyl, tetrazolyl and the like; heterocyclyl groups such as aziridinyl, pyrrolidinyl, morpholinyl, piperidinyl and the like; alkoxycarbonyl such as methoxycarbonyl or ethoxycarbonyl; aryloxycarbonyl group such as phenoxycarbonyl; amino(C₁ -C₆)alkyl; hydroxy(C₁ -C₆)alkyl; thio(C₁ -C₆)alkyl; or acyl group such as acetyl, propionyl, benzoyl, and the like.

All of the preferred groups that may represent R¹, R² and R³ may be substituted or unsubstituted.

When the groups represented by R¹, R² and R³ are substituted, the substituents selected are from the same groups as those groups that represent R¹, R² and R³ and may be selected from halogen, hydroxy, or nitro, or optionally substituted groups selected from alkyl, cycloalkyl, alkoxy, cycloalkoxy, aryl, aralkyl, heterocyclyl, heteroaryl, heteroaralkyl, acyl, acyloxy, hydroxyalkyl, amino, acylamino, arylamino, aminoalkyl, aryloxy, alkoxycarbonyl, alkylamino, alkoxyalkyl, alkylthio, thioalkyl groups, carboxylic acid or its derivatives, or sulfonic acid or its derivatives.

Suitable ring structure formed by any two of R¹, R² and R³ along with the adjacent atoms to which they are attached, include substituted or unsubstituted 4-7 membered cyclic structure which may contain one or more double bonds, the cyclic structure may be carbocyclic or optionally contains one or more hetero atoms selected from nitrogen, oxygen and sulfur. Examples of the cyclic structures are phenyl, naphthyl, thienyl, furyl, pyrrolyl, oxazolyl, oxadiazolyl, thiazolyl, imidazolyl, azacyclobutenyl, isoxazolyl, azepinyl, pyridyl, pyridazyl, pyrimidinyl, dihydrofuryl, dihydrothienyl, tetrahydropyridyl, tetrahydrophenyl, tetrahydronaphthyl and the like. The substituents on the cyclic structure may be selected from the same groups as that of R¹, R² and R³. Examples of possible substituents are halogen, alkyl, cycloalkyl, alkoxy, cycloalkoxy, aryl, aralkyl, heterocyclyl, heteroaryl, heteroaralkyl, hydroxy, acyl, acyloxy, hydroxyalkyl, amino, acylamino, arylamino, aminoalkyl, aryloxy, alkoxycarbonyl, alkylamino, alkoxyalkyl, carboxylic acid or its derivatives, or sulfonic acid or its derivatives.

It is more preferred that R¹, R² and R³ groups represent hydrogen; halogen atom such as fluorine, chlorine, bromine, or iodine; alkyl group such as methyl, ethyl, n-propyl or n-butyl; cycloalkyl group such as cyclopropyl; aryl group such as phenyl; or aralkyl group such as benzyl.

When the groups represented by R¹, R² and R³ are substituted, it is preferred that the substituents are selected from halogen, haloalkyl, haloalkoxy, and halocycloalkoxy wherein the halogen atom is preferably a fluorine atom.

The ring structure formed by any two of R¹, R² and R³ along with the adjacent atoms to which they are attached, may be substituted or unsubstituted. Preferred ring structures are phenyl, thienyl, furyl or pyridyl groups. When these ring structures are substituted, it is preferred that the substituents are selected from halogen, lower alkyl group such as methyl or ethyl; trifluoromethyl; fluoromethyl; difluoromethyl; and alkoxy groups such as methoxy, trifluoromethoxy, fluoromethoxy and difluoromethoxy.

The linking group --(CH₂)_(n) --O-- may be linked either through a nitrogen atom or through X, Y or Z. The integer n may range from 1 to 4, preferably n is 1 to 2. It is preferred that the linking group be linked either through nitrogen or through Z when Z represents ═C.

It is preferred that the group represented by Ar be substituted or unsubstituted divalent phenylene, naphthylene, pyridyl, quinolinyl, benzofuryl, dihydrobenzofuryl, benzopyranyl, indolyl, indolinyl, azaindolyl, azaindolinyl, pyrazolyl, benzothiazolyl, benzoxazolyl and the like. The substituents on the group represented by Ar may be selected from linear or branched (C₁ -C₆)alkyl, (C₁ -C₃)alkoxy, halogen, acyl, amino, acylamino, thio, or carboxylic or sulfonic acids or their derivatives.

It is more preferred that Ar represents substituted or unsubstituted divalent phenylene, naphthylene, benzofuryl, indolinyl, quinolinyl, azaindolyl, azaindolinyl, benzothiazolyl or benzoxazolyl.

It is still more preferred that Ar is represented by divalent phenylene or naphthylene, which may be optionally substituted by methyl, halomethyl, methoxy or halomethoxy groups.

Suitable R⁴ includes hydrogen; lower alkyl group such as methyl, ethyl or propyl; halogen atom such as fluorine, chlorine, bromine or iodine, or R⁴ together with A represents a bond.

Suitable A group may be nitrogen or CR⁵ where R⁵ may be a hydrogen atom, halogen, lower alkyl group or together with R⁴ forms a bond.

Suitable B group includes a hetero atom selected from O or S, with the provision that when A is CR⁵, B is selected from sulfur or oxygen, and when A is nitrogen, B represents oxygen.

Pharmaceutically acceptable salts forming part of this invention include salts of the azolidinedione moiety such as alkali metal salts like Li, Na, and K salts and salts of carboxy group wherever appropriate, such as aluminum, alkali metal salts, alkaline earth metal salts, ammonium or substituted ammonium salts. Salts may include acid addition salts which are sulphates, nitrates, phosphates, perchlorates, borates, hydrohalides, acetates, tartrates, maleates, citrates, succinates, palmoates, methanesulphonates, benzoates, salicylates, hydroxynaphthoates, benzene sulfonates, ascorbates, glycerophosphates, ketoglutarates and the like. Pharmaceutically acceptable solvates may be hydrates or comprising other solvents of crystallization such as alcohols.

Particularly useful compounds according to the present invention includes: 5- 4- 2- 2,4-Dimethyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-butyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-ethyl-4-phenyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 3-ethyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!oxazolidine-2,4-dione, 5- 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!oxazolidine-2,4-dione, 5- 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!oxazolidine-2,4-dione, 2- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!-1,2,4-oxadiazolidine-3,5-dione, 2- 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!-1,2,4-oxadiazolidine-3,5-dione, 2- 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!-1,2,4-oxadiazolidine-3,5-dione, 5 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione sodium salt, 5 4- 2- 2-methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione sodium salt, 5 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione sodium salt, 5 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione sodium salt.

According to a feature of the present invention, there is provided a process for the preparation of novel intermediate of the general formula (III) ##STR23## where X, Y, Z, R¹, R², R³ and n are as defined earlier, --(CH₂)_(n) --O-- linker is attached to nitrogen atom, G represents --CHO or --NO₂ group which comprises, reacting a compound of the general formula (IV) ##STR24## where X, Y, Z, R¹, R² and R³ are as defined earlier and H atom is attached to one of the nitrogen atoms of the ring, with a compound of general formula (V)

    L.sup.1 --(CH.sub.2).sub.n --O--Ar--G                      (V)

where Ar and n are as defined earlier and L¹ may be a halogen atom such as Cl, Br, I or a leaving group such as methanesulfonate, trifluoromethanesulfonate, p-toluenesulfonate etc., and G represents CHO, or NO₂ group.

The reaction of a compound of general formula (IV) with a compound of general formula (V) to produce a compound of general formula (III) may be carried out in the presence of solvents such as DMSO, DMF, DME, THF, dioxane, ether and the like or a combination thereof. The reaction may be carried out in an inert atmosphere which is maintained by using inert gases such as N₂, Ar, He. The reaction may be effected in the presence of a base such as alkalis like sodium hydroxide, potassium hydroxide, alkali metal carbonates like sodium carbonate, potassium carbonate; alkali metal hydrides such as sodium hydride or potassium hydride; organometallic bases like n-butyl lithium, alkali metal amides like sodamide or mixtures thereof. The amount of base may range from 1 to 5 equivalents, based on the amount of the compound of formula (IV), preferably the amount of base ranges from 1to 3 equivalents. 1 to 3 equivalents of alkali metal halides based on the amount of compound of formula (IV) such as lithium bromide may be added as an additive. The reaction may be carried out at a temperature in the range of 0° C. to 150° C., preferably at a temperature in the range of 15° C. to 100° C. The duration of the reaction may range from 0.25 to 24 hours, preferably from 0.25 to 6 hours.

In another embodiment of the invention, the novel intermediate of the general formula (III) defined and obtained above where G is CHO or NO₂ group, can be prepared by reacting the compound of the general formula (VI), ##STR25## wherein, X, Y, Z, R¹, R², R³ and n are as defined earlier, with a compound of general formula (VII)

    L.sup.2 --Ar--G                                            (VII)

where L² is a halogen atom, G is a CHO or a NO₂ group and Ar is as defined earlier.

The reaction of compound of formula (VI) with the compound of formula (VII) to produce a compound of formula (III) may be carried out in the presence of solvents such as THF, DMF, DMSO, DME and the like. The inert atmosphere is maintained by using inert gases such as N₂, Ar or He. The reaction may be effected in the presence of a base such as K₂ CO₃, Na₂ CO₃, NaH. The reaction temperature may range from 20° C. to 150° C., preferably at a temperature in the range of 30° C. to 100° C. The duration of the reaction may range from 1 to 24 hours, preferably from 2 to 6 hours.

In another embodiment of the present invention, the novel intermediate of general formula (III), where G is a CHO or NO₂ group, can also be prepared by the reaction of compound of general formula (VIII) ##STR26## where X, Y, Z, R¹, R², R³, n and L¹ are as defined earlier with a compound of general formula (IX)

    HO--Ar--G                                                  (IX)

where G is a CHO or NO₂ group and Ar is as defined earlier.

The reaction of compound of formula (VIII) with compound of formula (IX) to produce a compound of the formula (III) may be carried out in the presence of solvents such as THF, DMF, DMSO, DME and the like or mixtures thereof. The reaction may be carried out in an inert atmosphere which is maintained by using inert gases such as N₂, Ar, or He. The reaction may be effected in the presence of a base such as K₂ CO₃, Na₂ CO₃ or NaH or mixtures thereof. The reaction temperature may range from 20° C.-120° C., preferably at a temperature in the range of 30° C.-100° C. The duration of the reaction may range from 1-12 hours, preferably from 2 to 6 hours.

The present invention provides a process for the preparation of novel azolidinedione derivatives of general formula (I), their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts and their pharmaceutically acceptable solvates wherein R¹, R², R³, X, Y, Z, n and Ar are as defined earlier and A represents CR⁵ where R⁵ together with R⁴ represent a bond and B represents a sulfur or a oxygen atom, which comprises:

reacting the novel intermediate of the general formula (III) obtained above where G represents CHO group with 2,4-thiazolidinedione or 2,4-oxazolidinedione and removing the water formed during the reaction by conventional methods to yield a compound of general formula (X) ##STR27## where R¹, R², R³, X, Y, Z, n and Ar are as defined earlier and B represents sulfur or oxygen.

The reaction between the compound of the general formula (II) where G is a CHO group with 2,4-thiazolidinedione or 2,4-oxazolidinedione, to yield compound of general formula (X) wherein B represents a sulfur or an oxygen atom respectively, may be carried out neat in the presence of sodium acetate or in the presence of a solvent such as benzene, toluene, methoxyethanol or mixtures thereof. The reaction temperature may range from 80° C. to 140° C., depending upon the solvents employed and in the range from 80° C. to 180° C. when the reaction is carried out neat in the presence of sodium acetate. Suitable catalyst such as piperidinium acetate or benzoate, sodium acetate or mixtures of catalysts may also be employed. Sodium acetate can be used in the presence of solvent, but it is preferred that sodium acetate is used neat. The water produced in the reaction may be removed, for example, by using Dean Stark water separator or by using water absorbing agents like molecular seives. Oxazolidine-2-oxo-4-thione may be used instead of 2,4-oxazolidinedione. However, the thio group needs to be converted to oxo group by oxidation using agents such as hydrogen peroxide or peroxyacids like mCPBA.

The compound of the general formula (X) obtained in the manner described above is reduced by known method to obtain the compound of general formula (XI) ##STR28## wherein R¹, R², R³, X, Y, Z, n and Ar are as defined earlier and B represents a sulfur atom or an oxygen atom. The compound of general formula (XI) represents the compound of general formula (I), wherein R⁴ is hydrogen, A is CR⁵ where R⁵ is hydrogen and other symbols are as defined earlier.

The reduction of compound of the formula (X) to yield a compound of the general formula (XI) may be carried out in the presence of gaseous hydrogen and a catalyst such as Pd/C, Rh/C, Pt/C, and the like. Mixtures of catalysts may be used. The reaction may also be conducted in the presence of solvents such as dioxane, acetic acid, ethyl acetate and the like. A pressure between atmospheric pressure and 80 psi may be employed. The catalyst may be 5-10% Pd/C and the amount of catalyst used may range from 50-300% w/w. The reaction may also be carried out by employing metal solvent reduction such as magnesium in methanol or sodium amalgam in methanol.

The compound of the general formula (XI) obtained above is converted into its pharmaceutically acceptable salts, or its pharmaceutically acceptable solvates by conventional methods.

In yet another embodiment of the present invention, the compound of the general formula (I) can also be prepared by reacting a compound of the general formula (VIII) defined above with a compound of general formula (XII) ##STR29## where R⁴, A, B and Ar are as defined earlier and R⁶ is hydrogen or a nitrogen protecting group which is removed after the reaction.

The reaction of compound of formula (VIII) with compound of formula (XII) to produce a compound of the formula (I) may be carried out in the presence of solvents such as THF, DMF, DMSO, DME and the like or mixtures thereof. The reaction may be carried out in an inert atmosphere which is maintained by using inert gases such as N₂, Ar or He. The reaction may be effected in the presence of a base such as K₂ CO₃, Na₂ CO₃ or NaH or mixtures thereof. The reaction temperature may range from 20° C.-120° C., preferably at a temperature in the range of 30° C.-80° C. The duration of the reaction may range from 1-12 hours, preferably from 2 to 6 hours.

In still another embodiment of the invention, the compound of the general formula (I), where --(CH₂)_(n) --O-- linker is attached to nitrogen atom can be prepared by reacting the compound of the general formula (IV) defined above with a compound of general formula (XIII) ##STR30## where L¹, n, Ar, A, B, R⁴ and R⁶ are as defined earlier and removal of the protecting group when R⁶ is a nitrogen protecting group.

The reaction of compound of general formula (IV) with a compound of general formula (XIII) to produce a compound of general formula (I) may be carried out in the presence of solvents such as THF, DMF, DMSO, DME and the like or mixtures thereof. The reaction may be carried out in an inert atmosphere which is maintained by using inert gases such as N₂, Ar or He. The reaction may be effected in the presence of a base such as alkalis like sodium hydroxide, or potassium hydroxide; alkali metal carbonates like sodium carbonate, or potassium carbonate; alkali metal hydrides such as sodium hydride; organometallic bases like n-butyl lithium; alkali metal amides like sodamide, or mixtures thereof. Multiple solvents and bases can be used. The amount of base may range from 1 to 5 equivalents, preferably 1 to 3 equivalents. 1 to 3 equivalents of alkali metal halides such as lithium bromide may be added as an additive. The reaction temperature may be in the range of 0° C. to 120° C., preferably at a temperature in the range of 20° C. to 100° C. The duration of the reaction may range from 0.5 to 24 hours, preferably from 0.5 to 6 hours.

In another embodiment of the invention, the compound of general formula (I), where the linker --(CH₂)_(n) --O-- is attached through Z, where Z represents ═C, and all other symbols are as defined earlier can be prepared by reacting the compound of general formula (XIV) ##STR31## where R¹, R², and R³ are as defined earlier, X represents C═O or C═S and Y represents C═C; or when R² and R³ together with Y form a cyclic structure as defined earlier, X represents C═O or C═S, Y represents C═C and R¹ is as defined earlier, with a compound of general formula (XV) ##STR32## where Ar, R⁴, A, B and n are as defined earlier, D may be --CN; --C(OR⁷)₃ where R⁷ is (C₁ -C₄)alkyl; --C(═O)--R⁸ where R⁸ may be selected from --OH, Cl, Br, I, --NH₂, --NHR, where R is a lower alkyl group such as methyl, ethyl, propyl and the like; or O--(C═O)--R⁹, where R⁹ may be a linear or branched (C₁ -C₅)alkyl group such as methyl, ethyl, propyl, isopropyl, butyl, t-butyl and the like. The reaction proceeds through the intermediate formation of compound of general formula (XVa). ##STR33## The group X--NHR¹ in formula (XVa) can also be generated by conventional methods such as amidation of an ester group (XOR) or partial hydrolysis of a CN (in a compound where CN group is present in the place of X--NHR¹) group.

The reaction of compound of general formula (XIV) with a compound of general formula (XV) to produce a compound of general formula (I) may be carried out in neat or in the presence of solvents such as THF, dioxane, acetic acid and the like or mixtures thereof. The reaction may be carried out in an inert atmosphere which is maintained by using inert gases such as N₂, Ar or He. The reaction may be carried out at a temperature in the range of 25° C. to 250° C., preferably at a temperature in the range of 60° C. to 200° C. The reaction may be effected in the presence or in absence of a base or an acid. The nature of the base or the acid is not critical and any such base or acid commonly used in reactions of this type may be employed here. Example of such bases include organic bases such as pyridine, triethylamine and the like, metal carbonates such as K₂ CO₃, Na₂ CO₃. Examples of acids include organic acids such as AcOH, C₂ H₅ COOH and the like, mineral acids such as HCl, HBr etc. The duration of the reaction may range from 0.25 to 24 hours, preferably from 0.30 to 12 hours.

In another embodiment of the present invention, the compound of general formula (I), where R¹, R², R³, X, Y, Z, n and Ar are as defined earlier and A is CH and B represents S or O can be prepared by the reaction of compound of general formula (XVI) ##STR34## where R¹, R², R³, X, Y, Z, n and Ar are as defined earlier, J is a halogen atom like chlorine, bromine or iodine or a hydroxy group and R is a lower alkyl group, with urea when J is a OH group and with thiourea when J is a halogen atom, followed by treatment with an acid.

The reaction of compound of general formula (XVI) with urea or thiourea is normally carried out in the presence of alcoholic solvent such as methanol, ethanol, propanol, isobutanol, 2-methoxybutanol, etc or DMSO or sulfolane. The reaction may be conducted at a temperature in the range between 20° C. and the reflux temperature of the solvent used. Bases such as NaOAc, KOAc, NaOMe, NaOEt etc. can be used. The reaction is normally followed by treatment with a mineral acid such as hydrochloric acid at 20°-100° C.

The compound of general formula (XVI) where J is hydroxy group is prepared by the hydrolysis of compound of general formula (XVI) where J is a halogen atom using aqueous alkali at a temperature ranging from 20°-100° C. followed by reesterification of the hydrolysed acid group by conventional methods.

The compound of general formula (XVI) where J is a OH group may also be prepared from compound of formula (XVI) where J is a halogen atom by reacting with formamide in the presence of water. The amount of formamide used in the reaction ranges from 0.5 to 1.5 mL and water used ranges from 20 μL to 0.1 mL for one mmol of the halo compound (XVI). The reaction is conducted at a temperature ranging from 80° C. to 180° C., preferably from 120° C.-150° C., over a period ranging from 1 to 8 hours.

The compound of general formula (XVI) where J is a halogen atom can be prepared by the diazotization of the amino compound of the general formula (XVII) ##STR35## where all symbols are as defined earlier, using alkali metal nitrites followed by treatment with acrylic acid esters in the presence of hydrohalo acids and catalytic amount of copper oxide or copper halide.

The compound of general formula (XVII) can in turn be prepared by the conventional reduction of the novel intermediate (III) where G is NO₂ group and other symbols are as defined earlier.

In yet another embodiment of the present invention, the compound of general formula (I), where R¹, R², R³, X, Y, Z, n and Ar are as defined earlier and A is nitrogen atom and B is oxygen atom can be prepared by a process which comprises: reaction of novel intermediate of formula (III) where all symbols are as defined above, and G represents a CHO group with NH2OH.HCl to yield a compound of general formula (III) where G represents CH═NOH group and all symbols are as defined earlier, followed by metal borohydride reduction to yield a compound of general formula (XVIII) ##STR36## where all symbols are as defined earlier.

The reaction of compound of general formula (III), where G is CHO group and other symbols are as defined earlier, with hydroxylamine hydrochloride is carried out in solvents such as ethanol, methanol, THF, dioxane and the like following the conventional method to make oximes. 1 to 10 equivalents of NH₂ OH.HCl may be used, preferably, 2 to 5 equivalents. Bases such as alkali metal acetates or ammonium acetate may be used. Reaction may be carried out in the presence of water. Temperature in the range of 0° C. to reflux temperature of the solvent may be used. The oxime obtained in the manner described above is reduced using reducing agents such as alkali metal borohydrides like sodium borohydride or sodium cyanoborohydride or borane reagents using conventional conditions to yield the compound of general formula (XVIII).

The compound of general formula (XVIII) in turn is reacted with halocarbonyl isocyanate or alkoxycarbonyl isocyanate to yield a compound of general formula (I) or with KOCN to yield a compound of general formula (III) where G is CH₂ N(OH)CONH₂, followed by treatment with carbonylating agents such as alkylhaloformate to produce the compound of general formula (I) where R¹, R², R³, X, Y, Z, n, Ar are as defined earlier, A represents nitrogen atom and B is oxygen atom.

The reaction of compound of general formula (XVIII) with halocarbonyl isocyanate such as chlorocarbonyl isocyanate or alkoxycarbonyl isocyanate such as ethoxycarbonyl isocyanate may be carried out in inert solvents such as THF, dioxane, etc. at a temperature in the range -15° C. to 50° C. The reaction may be carried out for 0.5 to 12 hours depending on the substrates used for the reaction.

Alternatively, the compound of general formula (XVIII) may be treated with excess of KOCN in organic acids such as acetic acid. Water may be used in the reaction. The reaction may be carried out at a temperature in the range of 20° C. to 120° C. The product isolated in the reaction is further treated with alkyl haloformate such as ethyl chloroformate in the presence of 1 to 10 equivalents of alkali such as sodium hydroxide, potassium hydroxide and the like to obtain compound of general formula (I) where all the symbols are as defined earlier and A represents nitogen atom and B represents oxygen atom.

The pharmaceutically acceptable salts are prepared by reacting the compound of formula (I) with 1 to 4 equivalents of a base such as sodium hydroxide, sodium methoxide, sodium hydride in solvents like ether, THF, methanol etc. Alternatively, they are prepared by treatment with acids such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphonic acid, p-toluenesulphonic acid, methanesulfonic acid, acetic acid, citric acid, maleic acid salicyclic acid, hydroxynaphthoic acid, ascorbic acid, palmitic acid, succinic acid, benzoic acid, benzene sulfonic acid, tartaric acid and the like in solvents like ethyl acetate, ether, alcohols, acetone, THF, dioxane etc.

The stereoisomers of the compounds forming the part of this invention may be prepared by resolving the mixture of stereoisomers by conventional methods. Some of the preferred methods include use of microbial resolution, resolving the diastereomeric salts formed with chiral acids such as mandelic acid, camphorsulfonic acid, tartaric acid, lactic acid and the like or chiral bases such as brucine, cinchona alkaloids and their derivatives and the like.

The present invention also provides a pharmaceutical composition, containing the compounds of the general formula (I), as defined above, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates in combination with the usual pharmaceutically employed carriers, diluents and the like, useful for the treatment and/or prophylaxis of diseases in which insulin resistance is the underlying pathophysiological mechanism such as type II diabetes, impaired glucose tolerance, dyslipidaemia, hypertension, coronary heart disease and other cardiovascular disorders including atherosclerosis; insulin resistance associated with obesity and psoriasis, for treating diabetic complications and other diseases such as polycystic ovarian syndrome (PCOS), certain renal diseases including diabetic nephropathy, glomerulonephritis, glomerular sclerosis, nephrotic syndrome, hypertensive nephrosclerosis, end-stage renal diseases and microalbuminuria as well as certain eating disorders, as aldose reductase inhibitors and for improving cognitive functions in dementia.

The pharmaceutical composition may be in the forms normally employed, such as tablets, capsules, powders, syrups, solutions, suspensions and the like, may contain flavourants, sweeteners etc. in suitable solid or liquid carriers or diluents, or in suitable sterile media to form injectable solutions or suspensions. Such compositions typically contain from 1 to 20%, preferably 1 to 10% by weight of active compound, the remainder of the composition being pharmaceutically acceptable carriers, diluents or solvents.

The compound of the formula (I) as defined above are clinically administered to mammals, including man, via either oral or parenteral routes. Administration by the oral route is preferred, being more convenient and avoiding the possible pain and irritation of injection. However, in circumstances where the patient cannot swallow the medication, or absorption following oral administration is impaired, as by disease or other abnormality, it is essential that the drug be administered parenterally. By either route, the dosage is in the range of about 0.10 to about 200 mg/kg body weight of the subject per day or preferably about 0.10 to about 30 mg/kg body weight per day administered singly or as a divided dose. However, the optimum dosage for the individual subject being treated will be determined by the person responsible for treatment, generally smaller doses being administered initially and thereafter increments made to determine the most suitable dosage.

Suitable pharmaceutically acceptable carriers include solid fillers or diluents and sterile aqueous or organic solutions. The active compound will be present in such pharmaceutical compositions in the amounts sufficient to provide the desired dosage in the range as described above. Thus, for oral administration, the compounds can be combined with a suitable solid or liquid carrier or diluent to form capsules, tablets, powders, syrups, solutions, suspensions and the like. The pharmaceutical compositions, may, if desired, contain additional components such as flavourants, sweeteners, excipients and the like. For parenteral administration, the compounds can be combined with sterile aqueous or organic media to form injectable solutions or suspensions. For example, solutions in sesame or peanut oil, aqueous propylene glycol and the like can be used, as well as aqueous solutions of water-soluble pharmaceutically-acceptable acid addition salts of the compounds. The injectable solutions prepared in this manner can then be administered intravenously, intraperitoneally, subcutaneously, or intramuscularly, with intramuscular administration being preferred in humans.

The invention is explained in detail in the examples given below which are provided by way of illustration only and therefore should not be construed to limit the scope of the invention.

PREPARATION 1 4- 2- 4-Methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde ##STR37##

To a stirred suspension of NaH (570 mg, 22.57 mmol, 95%) in dry DMF (35 ml) at 25° C. was added a solution of 4-methyl-2-propyl-1,6-dihydro-6-pyrimidone (2.64 g, 17.36 mmol) in dry DMF. After the effervescence has ceased, anhydrous LiBr (3.51 g, 40.0 mmol) was added followed by 4- 2-bromoethoxy!benzaldehyde (4.37 g, 19.08 mmol) in dry DMF at the same temperature. The reaction mixture was immersed in a preheated oil bath at 70° C. and stirred for 2 h. The reaction mixture was cooled to room temperature, poured into water and extracted with EtOAc. The combined EtOAc layers were washed with brine, dried over anhydrous Na₂ SO₄ and concentrated. The crude compound was chromatographed over silica gel using 3:7 EtOAc-pet. ether as eluent to obtain the title compound (1.61 g, 31%).

¹ H NMR (CDCl₃): δ 9.80 (s, 1H), 7.82 (d, J=8.72 Hz, 2H), 6.95 (d, J=8.72 Hz, 2H), 620 (s, 1H), 4.45 (t, J=5.30 Hz, 2H), 4.35 (t, J=5.30 Hz, 2H), 2.92 (t, J=7.50 Hz, 2H), 2.25 (s, 3H), 1.92-1.70 (m, 2H), 1.20 (t, J=7.50 Hz, 3H).

PREPARATION 2 4- 2- 2,4-Dimethyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde ##STR38##

The title compound (0.8 g, 30%) was prepared from 2,4-dimethyl-1,6-dihydro-6-pyrimidone (1.3 g, 10.48 mmol) and 4- 2-bromoethoxy!benzaldehyde (2.4 g, 10.48 mmol) in the presence of a base K₂ C₃ (2.89 g, 20.96 mmol) by a similar procedure as described in preparation 1.

¹ H NMR (CDCl₃): δ 9.90 (s, 1H), 7.80 (d, J=8.70 Hz, 2H), 7.02 (d, J=8.70 Hz, 2H), 6.20 (s, 1H), 4.50-4.30 (m, 4H), 2.70 (s, 3H), 2.20 (s, 3H).

PREPARATION 3 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde ##STR39##

The title compound (1.7 g, 42%) was prepared from 2-ethyl-4-methyl-1,6-dihydro-6-pyrimidone (2.0 g, 14.49 mmol), 4- 2-bromoethoxy!benzaldehyde (3.32 g, 14.49 mmol), LiBr (2.9 g, 33.33 mmol) and NaH (0.45 g, 18.84 mmol) as base, by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.90 (s, 1H), 7.80 (d, J=8.70 Hz, 2H), 6.98 (d, J=8.70 Hz, 2H), 6.20 (s, 1H), 4.52-4.25 (m, 4H), 3.02 (q, J=7.40 Hz, 2H), 2.30 (s, 3H), 1.40 (t, J=7.40 Hz, 3H).

PREPARATION 4 4- 2- 2-Butyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde ##STR40##

The title compound (1.1 g, 25%) was prepared from 2-butyl4-methyl-1,6-dihydro-6-pyrimidone (2.3 g, 13.85 mmol), 4- 2-bromoethoxy!benzaldehyde (3.17 g, 13.85 mmol) in the presence of K₂ CO₃ (3.82 g, 27.7 mmol) as base by a similar procedure to that described in preparation 1.

¹ H NMR CDCl₃ : δ 9.90 (s, 1H), 7.84 (d, J=8.72 Hz, 2H), 6.98 (d, J=8.72 Hz, 2H), 6.20 (s, 1H), 4.52-4.30 (m, 4H), 2.96 (t, J=7.47 Hz, 2H), 2.26 (s, 3H), 1.90-1.70 (m, 2H), 1.70-1.50 (m, 2H), 1.01 (t, J=7.47 Hz, 3H).

PREPARATION 5 4- 2- 2-Benzyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde ##STR41##

The title compound (2.0 g, 20.6%) was prepared from 2-benzyl-4-methyl-1,6-dihydro-6-pyrimidone (5.6 g, 28.0 mmol), 4- 2-bromoethoxy!benzaldehyde (17.05 g, 30.1 mmol) in the presence of 95% NaH (873 mg, 35.0 mmol) as base by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.89 (s, 1H), 7.83 (d, J=8.72 Hz, 2H), 7.45-7.15 (m, 5H), 6.98 (d, J=8.72 Hz, 2H), 6.44 (s, 1H), 4.70 (t, J=4.71 Hz, 2H), 4.30 (t, J=4.71 Hz, 2H), 4.14 (s, 2H), 2.42 (s, 3H).

PREPARATION 6 4- 2- 2,5-Diethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde ##STR42##

The title compound (1.42 g, 28%) was prepared from 2,5-diethyl-4-methyl-1,6-dihydro-6-pyrimidone (2.70 g, 16.26 mmol) and 4- 2-bromoethoxy!benzaldehyde (4.09 g, 17.86 mmol) in the presence of 95% NaH (508 mg, 20 mmol) as base by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.88 (s, 1H), 7.82 (d, J=8.62 Hz, 2H), 6.97 (d, J=8.62 Hz, 2H), 4.50-4.20 (m, 4H), 2.95 (q, J=7.47 Hz, 2H), 2.52 (q, J=7.47 Hz, 2H), 2.28 (s, 3H), 1.34 (t, J=7.47 Hz, 3H), 1.09 (t, J=7.47 Hz, 3H).

PREPARATION 7 4- 2- 2-Ethyl-4-phenyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde ##STR43##

The title compound (2.0 g, 44%) was prepared from 2-ethyl-4-phenyl-1,6-dihydro-6-pyrimidone (2.6 g, 13.0 mmol), 4- 2-bromoethoxy!benzaldehyde (2.97 g, 13.0 mmol) and LiBr (2.59 g, 29.9 mmol) in the presence of NaH as base (0.4 g, 16.9 mmol) by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.89 (s, 1H), 8.10-7.95 (m, 2H), 7.83 (d, J=8.72 Hz, 2H), 7.55-7.45 (m, 3H), 6.98 (d, J=8.72 Hz, 2H), 6.78 (s, 1H), 4.60-4.40 (m, 4H), 3.08 (q, J=7.30 Hz, 2H), 1.48 (t, J=7.30 Hz, 3H).

PREPARATION 8 4- 2- 4-N-Acetylamino-2-oxo-1,2-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde ##STR44##

The title compound (1.8 g, 66%) was prepared from 4-acetylamino-1,2-dihydro-2-pyrimidone (1.8 g, 11.9 mmol) and 4- 2-bromoethoxy!benzaldehyde (2.72 g, 11.9 mmol) in the presence of K₂ CO₃ (3.28 g, 23.8 mmol) as base by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.90 (s, 1H), 8.70 (bs, 1H, D₂ O exchangeable), 7.85 (d, J=8.70 Hz, 2H), 7.75 (d, J=7.80 Hz, 1H), 7.42 (d, J=7.80 Hz, 1H), 6.95 (d, J=8.70 Hz, 2H), 4.40-4.20 (m, 4H), 2.30 (s, 3H).

PREPARATION 9 4- 2- 4-Oxo-3,4-dihydro-3-quinazolinyl!ethoxy!benzaldehyde ##STR45##

The title compound (1.5 g, 73%) was prepared from 4-oxo-3,4-dihydroquinazoline (1.03 g, 7.05 mmol) and 4- 2-bromoethoxy!benzaldehyde (1.77 g, 7.7 mmol) in the presence of K₂ CO₃ (2.0 g, 14.5 mmol) as base, by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.88 (s, 1H), 8.32 (d, J=7.88 Hz, 1H), 8.21 (s, 1H), 7.88-7.70 (m, 2H), 7.82 (d, J=8.72 Hz, 2H), 7.60-7.42 (m, 1H), 7.00 (d, J=8.72 Hz, 2H), 4.55-4.25 (m, 4H).

PREPARATION 10 4- 2- 2-Methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!benzaldehyde ##STR46##

The title compound (0.6 g, 39%) was prepared from 2-methyl-4-oxo-3,4-dihydroquinazoline (0.8 g, 5 mmol) and 4- 2-bromoethoxy!benzaldehyde (1.37 g, 6 mmol) in the presence of K₂ CO₃ (1.38 g, 10.0 mmol) as base, by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.85 (s, 1H), 8.13 (d, J=8.0 Hz, 1H), 7.84-7.72 (m, 3H), 7.59-7.41 (m, 2H), 7.10 (d, J=7.0 Hz, 2H), 4.50-4.40 (m, 2H), 4.40-4.30 (m, 2H), 2.76 (s, 3H).

PREPARATION 11 4- 2- 2-Ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!benzaldehyde ##STR47##

The title compound (5.0 g, 27%) was prepared from 2-ethyl-4-oxo-3,4-dihydroquinazoline (9.2 g, 57.5 mmol) and 4-(2-bromoethoxy)benzaldehyde (14.5 g, 69.0 mmol) in the presence of K₂ CO₃ (14.6 g, 115.0 mmol) as base, by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.86 (s, 1H), 8.14 (d, J=8.0 Hz, 1H), 7.87-7.76 (m, 3H), 7.65-4.45 (m, 2H), 7.13 (d, J=8.0 Hz, 2H), 4.60-4.50 (m, 2H), 4.50-4.40 (m, 2H), 3.07 (q, J=7.0 Hz, 2H), 1.35 (t, J=7.0 Hz, 3H).

PREPARATION 12 4- 2- 8-Aza-2-methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!benzaldehyde ##STR48##

The title compound (0.26 g, 41%) was prepared from 8-aza-2-methyl-4-oxo-3,4-dihydro quinazoline (0.33 g, 2.0 mmol), 4- 2-bromoethoxy!benzaldehyde (0.52 g, 2.25 mmol) in the presence of K₂ CO₃ (0.57 g, 4.1 mmol) as base by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.87 (s, 1H), 9.02-8.90 (m, 1H), 8.58 (d, J=7.30 Hz, 1H), 7.82 (d, J=8.72 Hz, 2H), 7.48-7.35 (m, 1H), 6.97 (d, J=8.72 Hz, 2H), 4.58 (t, J=4.72 Hz, 2H), 4.43 (t, J=4.72 Hz, 2H), 2.91 (s, 3H).

PREPARATION 13 4- 3-Methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!benzaldehyde ##STR49##

A mixture of 4-hydroxybenzaldehyde (3.21 g, 26.3 mmol) and K₂ CO₃ (3.64 g, 26.3 mmol) in dry DMF (50 ml) was stirred for 15 min at 30° C. To the above stirred mixture a solution of 2-chloromethyl-3-methyl4-oxo-3,4-dihydroquinazoline (5.0 g, 24.0 mmol) was added and stirred further for 90 minutes at the same temperature. The reaction mixture was diluted with EtOAc (200 ml), washed with aqueous Na₂ CO₃ solution (3×50 ml) and then with brine, dried over anhydrous Na₂ SO₄ and concentrated to yield the title compound (5.08 g, 72%).

¹ H NMR (CDCl₃): δ9.89 (s, 1H), 8.29 (d, J=7.89 Hz, 1H), 7.85 (d, J=8.71 Hz, 2H), 7.80-7.62 (m, 2H), 7.52 (t, J=7.81 Hz, 1H), 7.19 (d, J=8.71 Hz, 2H), 5.27 (s, 2H), 3.74 (s, 3H).

PREPARATION 14 4- 3-Ethyl4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!benzaldehyde ##STR50##

The title compound (4.24 g, 88%) was prepared from 2-chloromethyl-3-ethyl-4-oxo-3,4-dihydro-quinazoline (3.5 g, 15.7 mmol) and 4-hydroxybenzaldehyde (2.10 g, 17.21 mmol) in the presence of K₂ CO₃ (2.38 g, 17.26 mmol) as base by a similar procedure to that described in preparation 13.

¹ H NMR (CDCl₃): δ 9.91 (s, 1H), 8.31 (d, J=7.89 Hz, 1H), 7.88 (d, J=8.72 Hz, 2H), 7.82-7.68 (m, 2H), 7.65-7.45 (m, 1H), 7.22 (d, J=8.72 Hz, 2H), 5.28 (s, 2H), 4.28 (q, J=7.06 Hz, 2H), 1.41 (t, J=7.06 Hz, 3H).

PREPARATION 15 4- 1-methyl-4-oxo-1,4-dihydro-2-quinazolinyl!methoxy!benzaldehyde ##STR51##

The title compound (364 mg, 65%) was prepared from 2-chloromethyl-1-methyl-4-oxo-1,4-dihydroquinazoline (416 mg, 2.0 nmmol) and 4-hydroxybenzaldehyde (244 mg, 2.0 mmol) in the presence of K₂ CO₃ (276 mg, 2.0 mmol) as base by a similar procedure to that described in preparation 13.

¹ H NMR (CDCl₃): δ 9.88 (s, 1H), 8.34 (d, J=7.89 Hz, 1H), 7.83 (d, J=8.71 Hz, 2H), 7.80-7.70 (m, 1H), 7.60-7.40 (m, 2H), 7.22 (d, J=8.71 Hz, 2H), 5.34 (s, 2H), 3.19 (s, 3H).

PREPARATION 16 3-Methoxy-4- 3-Methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!benzaldehyd ##STR52##

The title compound (250 mg, 77%) was obtained from 2-chloromethyl-3-methyl-4-oxo-3,4-dihydroquinazoline (209 mg, 1.0 mmol) and vanillin (167 mg, 1.1 mmol) in the presence of K₂ CO₃ (276 mg, 2.0 mmol) as base by a similar procedure to that described in preparation 13.

¹ H NMR (CDCl₃): δ 9.88 (s, 1H), 8.29 (d, J=8.30 Hz, 1H), 7.80-7.62 (m, 2H), 7.58-7.39 (m, 2H), 7.26 (d, J=8.30 Hz, 2H), 5.30 (s, 2H), 3.90 (s, 3H), 3.78 (s, 3H).

PREPARATION 17 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde oxime ##STR53##

To a stirred solution of hydroxylamine hydrochloride (10.0 g, 143.0 mmol) and sodium acetate trihydrate (20.0 g, 146.9 mmol) in water (100 ml) at 30° C. was added a hot solution of 4- 2- -2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (5.72 g, 20.0 mmol) (obtained from preparation 3) in ethanol (100 ml). The reaction mixture was immersed in a preheated oil bath (95° C.) and refluxed for 3 h. The reaction mixture was then cooled to room temperature and concentrated to a volume where crystals of oxime started separating out and the mixture was kept aside for 30 min. to 1 h at 25° C. The resultant crystals were filtered and washed with water and dried to obtain the title compound (5.42 g, 90%).

¹ H NMR (CDCl₁₃ +DMSO-d₆): δ 10.56 (s, 1H, OH, D₂ O exchangeable), 8.08 (s, 1H), 7.55 (d, J=8.56 Hz, 2H), 6.88 (d, J=8.56 Hz, 2H), 6.20 (s, 1H), 4.51-4.40 (m, 2H), 4.40-4.28 (m, 2H), 3.05 (q, J=7.06 Hz, 2H), 2.30 (s, 3H), 1.40 (t, J=7.06 Hz, 3H).

PREPARATION 18 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzylhydroxylamine ##STR54##

To a stirred solution of 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde oxime (301 mg, 1.0 mmol) (obtained from preparation 17) in a mixture of methanol (7 ml) and THF (3 ml) was added 4N HCl (2 ml) in dioxane at 30° C. and stirred for 10 min. at the same temperature. The reaction mixture was basified to pH 9 with 1N NaOH and extracted with EtOAc (3×10 ml). The combined organic layers were washed with brine and dried over anhydrous Na₂ SO₄ and concentrated to yield the of title compound (272 mg, 90%).

¹ H NMR (CDCl₃): δ 7.23 (d, J=8.72 Hz, 2H), 6.80 (d, J=8.72 Hz, 2H), 6.18 (s, 1H), 4,45-4.35 (m, 2H), 4.35-4.20 (m, 2H), 3.98 (s, 2H), 3.01 (q, J=7.56 Hz, 2H), 222 (s, 3H), 1.32 (t, J=7.56 Hz, 3H).

PREPARATION 19 N- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzyl!N-hydroxyurea ##STR55##

To a stirred solution of 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzyl hydroxylamine (303 mg, 1.0 mmol) (obtained from preparation 18) in a mixture of water (2 ml) and acetic acid (0.5 ml) was added a solution of KOCN (343 mg, 3.0 mmol) in water (1 ml) and stirred for 1 h at 30° C. The reaction mixture was diluted with water and extracted with ethyl acetate (3×10 ml). The combined organic layers were washed with brine, dried over anhydrous Na₂ SO₄ and concentrated to yield the compound (295 mg, 85%).

¹ H NMR (CDCl₃): δ 7.18 (d, J=8.65 Hz, 2H), 6.90 (d, J=8.65 Hz, 2H), 6.60 (bs, 1H, D₂ O exchangeable), 6.15 (s, 1H), 5.85 (bs, 1H, D₂ O exchangeable), 4.70 (s, 2H), 4.50 (bs, 1H, D₂ O exchangeable), 4.40-4.30 (m, 2H), 4.22-4.10 (m, 2H), 2.92 (q, J=7.56 Hz, 2H) 2.20 (s, 3H), 1.20 (t, J=7.56 Hz, 3H).

PREPARATION 20 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!nitrobenzene ##STR56##

The title compound (5.2 g, 25%) was prepared from 2-ethyl-4-methyl-1,6-dihydro-6-pyrimidone (7.65 g, 55.43 mmol), 4- 2-bromoethoxy!nitrobenzene (15.0 g, 60.97 mmol), LiBr (11.09 g, 127.49 mmol) and 60% NaH (2.76 g, 72.06 mmol) as base by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 8.20 (d, J=8.81 Hz, 2H), 6.94 (d, J=8.81 Hz, 2H), 6.22 (s, 1H), 4.55-4.42 (m, 2H), 4.42-4.34 (m, 2H), 2.99 (q, J=7.4 Hz, 2H), 2.27 (s, 3H), 1.38 (t, J=7.4 Hz, 3H).

PREPARATION 21 4- 2- 2-Ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!nitrobenzene ##STR57##

The title compound (1.246 g, 64%) was prepared from 2-ethyl-4-oxo-3,4-dihydroquinazoline (1.0 g, 5.7 mmol) and 4- 2-bromoethoxy!nitrobenzene (1.696 g, 6.8 mmol) and K₂ CO₃ (1.58 g, mmol) as a base by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 8.24 (d, J=7.93 Hz, 1H), 8.18 (d, J=9.20 Hz, 2H), 7.82-7.61 (M, 2H), 7.46 (t, J=7.93 Hz, 1H), 6.94 (d, J=9.20 Hz, 2H), 4.58 (t, J=4.82 Hz, 2H), 4.44 (t, J=4.82 Hz, 2H), 3.09 (q, J=7.38 Hz, 2H), 1.46 (t, J=7.38 Hz, 3H).

PREPARATION 22 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!aniline ##STR58##

A solution of 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!nitrobenzene (1.0 g, 3.3 mmol) (obtained from preparation 20) in 1,4-dioxane (20 ml) was reduced with hydrogen in the presence of 10% palladium on charcoal (100 mg) at 30 psi for 16 h. The mixture was filtered through a bed of celite and washed with dioxane and evaporated to dryness under reduced pressure to yield the title compound (625 mg, 70%).

¹ H NMR (CDCl₃): δ 6.78-6.52 (m, 4H), 6.18 (s, 1H), 4.38 (t, J=4.98 Hz, 2H), 4.19 (t, J=4.98 Hz, 2H), 2.99 (q, J=7.47 Hz, 2H), 2.24 (s, 3H), 1.33 (t, J=7.47 Hz, 3H).

PREPARATION 23 4- 2- 2-Ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!aniline ##STR59##

The title compound (1.107 g, 98%) was prepared from 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!nitrobenzene (1.246 g, 3.67 mmol) (obtained from preparation 21) by a similar procedure to that described in preparation 22.

¹ H NMR (CDCl₃): δ 8.24 (d, J=7.93 Hz, 1H), 7.80-7.60 (m, 2H), 7.43 (t, J=7.93 Hz, 1H), 6.80-6.50 (m, 4H), 4.51 (t, J=5.19 Hz, 2H), 4.24 (t, J=5.19 Hz, 2H), 3.10 (q, J=7.43 Hz, 2H), 1.42 (t, J=7.34 Hz, 3H).

PREPARATION 24 Ethyl 2-bromo-3- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl!propionate ##STR60##

To a stirred solution of 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!aniline (2.80 g, 10.26 mmol) (obtained from preparation 22) in acetone (10 ml) was added aqueous HBr (47%, 1 ml) and stirred for 10 min. at 0° C. To the above reaction mixture a solution of NaNO₂ (850 mg, 12.30 mmol) in water (1.7 ml) was added slowly dropwise at 0° C. and stirring was continued further for 30 min at the same temperature. To this reaction mixture, ethyl acrylate (6.77 ml, 62.0 mmol) was added and allowed to warm to 30° C. Catalytic amount of copper (I) iodide (20 mg) was added in one portion and the reaction mixture was stirred further for 1 h at 30° C. Acetone was removed under reduced pressure and the resultant residue was extracted with EtOAc (3×10 ml). The combined EtOAc layers were washed with dilute NH₃ solution, water, followed by brine; dried over anhydrous Na₂ SO₄ and concentrated to afford the crude compound which was purified by flash chromatography using 40% EtOAc/petroleum ether as eluent to yield the title compound (2.47 g, 55%).

¹ H NMR (CDCl₃): δ 7.11 (d, J=8.63 Hz, 2H), 6.78 (d, J=8.63 Hz, 2H), 6.19 (s, 1H), 4.50-4.32 (m, 2H), 4.30-4.02 (m, 5H), 3.38 (dd, J=13.72, 8.31 Hz, 1H), 3.17, (dd, J=13.72, 7.06 Hz, 1H), 3.10-2.90 (m, 2H), 2.25 (s, 3H), 1.35 (t, J=7.47 Hz, 3H), 1.24 (t, J=7.05 Hz, 3H).

PREPARATION 25 Ethyl 2-bromo-3- 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl!propionate ##STR61##

The title compound (671 mg, 55%) was prepared from 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!aniline (800 mg, 2.58 mmol) (obtained from preparation 23), NaNO₂ (214 mg, 3.1 mmol) and ethyl acrylate (1.7 ml, 1.574 g, 15.74 mmol) by a similar procedure to that described in preparation 24.

¹ H NMR (CDCl₃): δ 8.23 (d, J=7.88 Hz, 1H), 7.80-7.55 (m, 2H), 7.15-7.01 (m, 2H), 6.77 (d, J=8.71 Hz, 2H), 4.52 (t, J=5.03 Hz, 2H), 4.45-4.30 (m, 1H),430 (t, J=5.03 Hz, 2H), 4.20-4.00 (m, 2H), 3.35 (dd, J=14.12, 8.71 Hz, 1H), 3.20-3.00 (m, 3H), 1.43 (t, J=7.34 Hz, 3H), 1.20 (t, J=7.34 Hz, 3H).

PREPARATION 26 5- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!-2-iminothiazolidine-4-one hydrochloride ##STR62##

A mixture of ethyl 2-bromo-3- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl!propionate (1.70 g, 3.89 mmol) (obtained from preparation 24), fused, sodium acetate (637 mg, 7.78 mmol) and thiourea (592 mg, 7.78 mmol) in ethanol (10 ml) was refluxed for 12 h. The reaction mixture was cooled to room temperature and the resultant solid was filtered and dried to afford the title compound (1.35 g, 89%).

¹ H NMR (CDCl₃): δ 7.12 (d, J=8.59 Hz, 2H), 6.76 (d, J=8.59 Hz, 2H), 6.12 (s, 1H), 4.50-4.30 (m, 3H), 4.30-4.15 (m, 2H), 3.40 (dd, J=14.11, 3.74 Hz, 1H), 2.98 (q, J=7.47 Hz, 2H), 2.85 (dd, J=14.11, 9.43 Hz, 1H), 2.23 (s, 3H), 1.32 (t, J=7.47 Hz, 3H).

PREPARATION 27 5- 4- 2- 2-Ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!-2-imino thiazolidine-4-one hydrochloride ##STR63##

The title compound (329 mg, 78%) was prepared from ethyl 2-bromo-3- 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl!propionate (473 mg, 1.0 mmol) (obtained from preparation 25), sodium acetate (164 mg, 2.0 mmol) and thiourea (152 mg, 2.0 mmol) by a similar procedure to that described in preparation 26.

¹ H NMR (CDCl₃): δ 8.12 (d, J=7.88 Hz, 1H), 7.80 (t, J=7.03 Hz, 1H), 7.62 (d, J=7.88 Hz, 1H), 7.49 (t, J=7.03 Hz, 1H), 7.12 (d, J=7.58 Hz, 2H), 6.84 (d, J=7.58 Hz, 2H), 4.50 (dd, J=9.43, 3.72 Hz, 1H), 4.46 (t, J=5.31 Hz, 2H), 4.25 (d, J=5.31 Hz, 2H), 3.25 (dd, J=14.11, 372 Hz, 1H), 3.04 (q, J=7.17 Hz, 2H), 2.81 (dd, J=14.11, 9.43 Hz, 1H), 1.31 (t, J=7.19 Hz, 3H).

PREPARATION 28 3- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl!-2-hydroxypropionic acid ##STR64##

A mixture of ethyl 2-bromo- 3- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl-ethoxy!phenyl!propionate (438 mg, 1.0 mmol) (obtained from preparation 24), sodium hydroxide (44 mg, 1.1 mmol) and calcium carbonate (100 mg, 1.0 mmol) in 1,4-dioxane (2 ml) and water (3 ml) was refluxed for 10 h. The reaction mixture was cooled to room temperature and acidified to pH 4 with 2N HCl and extracted with EtOAc (2×10 ml). The combined organic layers were washed with brine, dried over Na₂ SO₄ and concentrated to afford the title compound (92 mg, 27%).

¹ H NMR (CDCl₃ +DMSO-d₆): δ 7.12 (d, J=8.61 Hz, 2H), 6.78 (d, J=8.61 Hz, 2H), 6.19 (s, 1H), 4.50-4.32 (m, 2H), 4.30-4.05 (m, 3H), 3.10-2.60 (m, 4H), 2.25 (s, 3H), 1.30 (t, J=7.20 Hz, 3H).

PREPARATION 29 Ethyl 3- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl!-2-hydroxypropionate ##STR65## Method A

A solution of 3- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl!-2-hydroxypropionic acid (346 mg, 1.0 mmol) (obtained from preparation 28) in ethanol (3 ml) containing concentrated hydrochloric acid (0.1 ml) was refluxed for 10 h. The solution was cooled to room temperature, diluted with water and extracted with EtOAc (2×10 ml). The combined organic extracts were washed with brine, dried over anhydrous Na₂ SO₄ and concentrated to yield the title compound (97 mg, 26%).

Method B

A mixture of ethyl 2-bromo-3- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl!propionate (1.0 g, 2.28 mmol) (obtained from preparation 24) formamide (225 μl) and water (45 μl, 45 mg, 2.5 mmol) was heated at 160° C. for 3 h. Water (45 μl) was added further and stirred for 2 h at 175° C. The reaction mixture was cooled to room temperature, diluted with EtOAc (10 ml) washed with brine, dried over anhydrous Na₂ SO₄ and concentrated to yield the crude compound which was purified by flash chromatography to afford the title compound (306 mg, 36%).

¹ H NMR (CDCl₃): δ 7.11 (d, J=8.62 Hz, 2H), 6.77 (d, J=8.62 Hz, 2H), 6.18 (s, 1H), 4.50-4.31 (m, 2H), 4.30-4.05 (m, 5H), 3.10-2.80 (m, 4H), 2.25 (s, 3H), 1.40-1.15 (m, 6H).

PREPARATION 30 5- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!-2-thio-oxazolidine4-one ##STR66##

An intimate mixture of 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (286 mg, 1.0 mmol) (obtained from preparation 3), 2-thio-1,3-oxazolidine-4-one (175 mg, 1.5 mmol) and anhydrous sodium acetate (246 mg, 3.0 mmol) was heated at 120° C. under reduced pressure (2.0 torr.) for 90 min. After cooling, the reaction mixture was poured into ethyl acetate (80 ml) and water (20 ml) and stirred for 30 min, the aqueous layer was separated and acidified to pH 4 with 2N HCl. The solid separated was filtered and dried to yield the title compound (207 mg, 54%).

¹ H NMR (CDCl₃): δ 7.76 (d, J=8.62 Hz, 2H), 6.93 (d, J=8.62 Hz, 2H), 6.59 (s, 1H), 6.17 (s, 1H), 4.50-4.30 (m, 4H), 2.98 (q, J=7.47 Hz, 2H), 2.27 (s, 3H), 1.35 (t, J=7.47 Hz, 3H).

PREPARATION 31 4- 2,- 2,5,6-Trimethyl-4-oxo-3,4-dihydro-thieno- 2,3-d!pyrimidin-3-yl!ethoxy!benzaldehyde ##STR67##

The title compound (5.04 g, 27%) was prepared from 2,5,6-trimethyl-4-oxo-thienopyrimidine (10.59 g, 54.6 mmol), 4- 2-bromoethoxy!benzaldehyde (12.82 g, 56 mmol) and K₂ CO₃ (15.04 g, 109 mmol) as base by a similar procedure to that described in preparation 1.

¹ H NMR (CDCl₃): δ 9.88 (s, 1H), 7.82 (d, J=8.72 Hz, 2H), 6.98 (d, J=8.72 Hz, 2H), 4.60-4.30 (m, 4H), 2.78 (s, 3H), 2.46 (s, 3H), 2.37 (s, 3H).

EXAMPLE 1 5- 4- 2- 4-Methyl-2-Propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR68##

A mixture of 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (10) g, 24.5 mmol) (obtained from preparation 1), thiazolidine-2,4-dione (3.5 g, 30 mmol), benzoic acid (388 mg, 3.18 mmol) and piperidine (352 μl, 303 mg, 3.68 mmol) in toluene (50 ml) was refluxed for 1 h with continuous removal of water. The reaction mixture was cooled to room temperature and the resultant crystalline compound was filtered and washed with water and dried to afford the title compound (12.3 g, 99%), mp 240°-242° C.

¹ H NMR (DMSO-d₆): δ 12.40 (bs, 1H, D₂ O exchangeable), 7.75 (s, 1H), 7.54 (d, J=8.72 Hz, 2H), 7.02 (d, J=8.72 Hz, 2H), 6.15 (s, 1H), 4.45-4.15 (m, 4H), 2.91 (t, J=7.65 Hz, 2H), 220 (s, 3H), 1.90-1.65 (m, 2H), 1.06 (t, J=7.65 Hz, 3H).

EXAMPLE 2 5- 4- 2- 2,4-Dimethyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR69##

The title compound (0.98 g, 95%) was obtained from 4- 2- 2,4-dimethyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (0.8 g, 2.8 mmol) (obtained from preparation 2) and thiazolidine-2,4-dione (0.344 g, 2.8 mmol) by a similar procedure to that described in example 1, mp 235° C.

¹ H NMR (CDCl₃): δ 8.50 (bs, 1H, D₂ O exchangeable), 7.80 (s, 1H), 7.48 (d, J=8.40 Hz, 2H), 6.98 (d, J=8.40 Hz, 2H), 6.21 (s, 1H), 4.52-4.30 (m, 4H), 2.70 (s, 3H), 2.25 (s, 3H).

EXAMPLE 3 5- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR70##

The title compound (2.13 g, 92%) was obtained from 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (1.7 g, 5.94 mmol) (obtained from preparation 3) and thiazolidine-2,4-dione (0.695 g, 5.94 mmol) by a similar procedure to that described in example 1, mp 248°-250° C.

¹ H NMR (CDCl₃ +DMSO-d₆): δ 12.25 (bs, 1H, D₂ O exchangeable), 7.78 (s, 1H), 7.40 (d, J=7.40 Hz, 2H), 7.0 (d, J=7.40 Hz, 2H), 6.20 (s, 1H), 4.48-4.24 (m, 4H), 3.0 (q, J=6.4 Hz, 2H), 2.20 (s, 3H), 1.28 (t, J=6.4 Hz, 3H).

EXAMPLE 4 5- 4- 2- 2-Butyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR71##

The title compound (1.2 g, 83%) was obtained from 4- 2- 2-butyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (1.1 g, 3.5 mmol) (obtained from preparation 4) and thiazolidine-2,4-dione (410 mg, 3.5 mmol) by a similar procedure to that described in example 1, mp 209° C.

¹ H NMR (CDCl₃): δ 7.80 (s, 1H), 7.40 (d, J=8.63 Hz, 2H), 6.95 (d, J=8.63 Hz, 2H), 6.21 (s, 1H), 4.55-4.22 (m, 4H), 2.95 (t, J=7.47 Hz, 2H), 2.25 (s, 3H), 1.85-1.60 (m, 2H), 1.60-1.40 (m, 2H), 0.99 (t, J=7.10 Hz, 3H).

EXAMPLE 5 5- 4- 2- 2-Benzyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR72##

The title compound (1.70 g, 66%) was obtained from 4- 2- 2-benzyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (2.0 g, 5.74 mmol) (obtained from preparation 5) and thiazolidine-2,4-dione (0.74 g, 6.4 mmol) by a similar procedure to that described in example 1, mp 223° C.

¹ H NMR (CDCl₃ +DMSO-d₆): δ 7.74 (s, 1H), 7.44 (d, J=8.71 Hz, 2H), 7.40-7.10 (m, 5H), 6.95 (d, J=8.71 Hz, 2H), 6.26 (s, 1H), 4.38 (s, 2H), 4.35-4.10 (m, 4H), 2.32 (s, 3H).

EXAMPLE 6 5- 4- 2- 2,5-Diethyl4methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4dione ##STR73##

The title compound (881 mg, 92%) was obtained from 4- 2- 2,5-diethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (730 mg, 2.32 mmol) (obtained from preparation 6) and thiazolidine-2,4-dione (451 mg, 2.55 mmol) by a similar procedure to that described in example 1, mp 252°-254° C.

¹ H NMR (CDCl₃ +DMSO-d₆): δ 12.08 (bs, 1H, D₂ O exchangeable), 7.69 (s, 1H), 7.44 (d, J=8.58 Hz, 2H), 6.97 (d, J=8.58 Hz, 2H), 4.50-4.20 (m, 4H), 2.93 (q, J=7.43 Hz, 2H), 2.50 (q, J=7.43 Hz, 2H), 2.26 (s, 3H), 1.33 (t, J=7.43 Hz, 3H), 1.07 (t, J=7.43 Hz, 3H).

EXAMPLE 7 5- 4- 2- 2-Ethyl-4-phenyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR74##

The title compound (2.2 g, 88%) was obtained from 4- 2- 2-ethyl-4-phenyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (2.09 g, 6.0 mmol) (obtained from preparation 7) and thiazolidine-2,4-dione (0.702 g, 6.0 mmol) by a similar procedure to that described in example 1, mp 234° C.

¹ H NMR (DMSO-d₆): δ 12.58 (bs, 1H, D₂ O exchangeable), 8.22-8.05 (m, 2H), 7.74 (s, 1H), 7.66-7.38 (m, 5H), 7.11 (d, J=8.30 Hz, 2H), 6.92 (s, 1H), 4.48-4.20 (m, 4H), 3.06 (q, J=7.06 Hz, 2H), 1.35 (t, J=7.06 Hz, 3H).

EXAMPLE 8 5- 4- 2- 4-Oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR75##

The title compound (1.91 g, 84%) was obtained from 4- 2- 4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!benzaldehyde (1.7 g, 5.78 mmol) (obtained from preparation 9) and thiazolidine-2,4-dione (678 mg, 5.79 mmol) by a similar procedure to that described in example 1, mp 242°-244° C.

¹ H NMR (CDCl₃ +DMSO-d₆): δ 12.56 (bs, 1H, D₂ O exchangeable), 8.42 (s, 1H), 8.18 (d, J=7.89 Hz, 1H), 7.84 (t, J=7.47 Hz, 1H), 7.72 (s, 1H), 7.72-7.50 (m, 2H), 7.54 (d, J=8.72 Hz, 2H), 7.11 (d, J=8.72 Hz, 2H), 4.40 (s, 4H).

EXAMPLE 9 5- 4- 2- 2-Methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR76##

The title compound (4.28, 93%) was obtained from 4- 2- 2-methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!benzaldehyde (3.4 g, 11.04 mmol) (obtained from preparation 10) and thiazolidine-2,4-dione (1.6 g, 13.8 mmol) by a similar procedure to that described in example 1, mp 278° C.

¹ H NMR (DMSO-d₆): δ 12.58 (bs, 1H, D₂ O exchangeable), 8.19 (d, J=8.0 Hz, 1H), 7.89-7.44 (m, 6H), 7.03 (d, J=8.7 Hz, 2H), 4.58-4.42 (m, 2H), 4.42-4.25 (m, 2H) 2.18 (s, 3H).

EXAMPLE 10 5- 4- 2- 2-Ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR77##

The title compound (0.42 g, 92%) was obtained from 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!benzaldehyde (0.35 g, 1.08 mmol) (obtained from preparation 11) and thiazolidine-2,4-dione (0.16 g, 1.4 mmol) by a similar procedure to that described in example 1, mp 257° C.

¹ H NMR (DMSO-d₆): δ 12.58 (bs, 1H, D₂ O exchangeable), 8.15 (d, J=8.0 Hz, 1H), 7.82-7.44 (m, 6H), 7.08 (d, J=8.0 Hz, 2H), 4.47-4.40 (m, 2H), 4.40-4.30 (m, 2H) 3.08 (q, J=7.0 Hz, 2H), 1.37 (t, J=7.0 Hz, 3H).

EXAMPLE 11 5- 4- 2- 8-Aza-2-methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR78##

The title compound (0.25 g, 68%) was obtained from 4- 2- 8-Aza-2-methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!benzaldehyde (0.28 g, 0.9 mmol) (obtained from preparation 12) and thiazolidine-2,4-dione (0.106 g, 0.9 mmol) by a similar procedure to that described in example 1, mp 276° C.

¹ H NMR (CDCl₃ +DMSO-d₆): δ 9.00-8.90 (m, 1H), 8.51 (d, J=7.30 Hz, 1H), 7.72 (s, 1H, 7.51 (d, J=8.72 Hz, 2H), 7.55-7.45 (m, 1H), 7.05 (d, J=8.72 Hz, 2H), 4.60-4.50 (m, 2), 4.50-4.38 (m, 2H), 2.85 (s, 3H).

EXAMPLE 12 5- 4- 3-Methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methylene!thiazolidine-2,4-dione ##STR79##

The title compound (11.10 g, 96%) was obtained from 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!benzaldehyde (9.0 g, 30.61 mmol) (obtained from preparation 13) and thiazolidine-2,4-dione (3.6 g, 30.61 mmol) by a similar procedure to that described in example 1, mp 280° C.

¹ H NMR (CDCl₃ +DMSO-d₆): δ 12.38 (bs, 1H, D₂ O exchangeable), 8.19 (d, J=7.47 Hz, 1Hz), 7.82-7.60 (m, 2H), 7.72 (s, 1H), 7.53 (d, J=8.7 Hz, 2H), 7.60-7.48 (m, 1H), 7.23 (d, J=8.72 Hz, 2H), 5.35 (s, 2H), 3.68 (s, 3H).

EXAMPLE 13 5- 4- 3-Ethyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methylene!thiazolidine-2,4-dione ##STR80##

The title compound (3.3 g, 83%) was obtained from 4- 3-ethyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!benzaldehyde (3.0 g, 9.74 mmol) (obtained from preparation 14) and thiazolidine-2,4-dione (1.14 g, 9.74 mmol) by a similar procedure to that described in example 1, mp 260°-261° C.

¹ H NMR (CDCl₃ +DMSO-d₆): δ 12.58 (bs, 1H, D₂ O exchangeable), 8.18 (d, J=7.88 Hz, 1H), 7.92-7.74 (m, 1H), 7.78 (s, 1H), 7.74-7.54 (m, 2H), 7.61 (d, J=8.72 Hz, 2H), 7.29 (d, J=8.72 Hz, 2H), 5.40 (s, 2H), 4.14 (q, J=6.84 Hz, 2H), 1.34 (t, J=6.84 Hz, 3H).

EXAMPLE 14 5- 4- 1-Methyl-4-oxo-1,4-dihydro-2-quinazolinyl!methoxy!phenyl methylene!thiazolidine-2,4-dione ##STR81##

The title compound (310 mg, 79%) was obtained from 4- 1-methyl-4-oxo-1,4-dihydro-2-quinazolinyl!methoxy!benzaldehyde (294 mg, 1.0 mmol) (obtained from preparation 15) and thiazolidine-2,4-dione (117 mg, 1.0 mmol) by a similar procedure to that described in example 1.

¹ H NMR (DMSO-d₆): δ 8.09 (d, J=7.88 Hz, 1H), 8.00-7.04 (m, 4H), 7.58 (d, J=8.72 Hz, 2H), 7.24 (d, J=8.72 Hz, 2H), 5.41 (s, 2H), 3.86 (s, 3H).

EXAMPLE 15 5- 3-Methoxy-4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methylene!thiazolidine-2,4-dione ##STR82##

The title compound (235 mg, 90%) was obtained from 3-methoxy-4- 3-methyl-4-oxo-3,4-dihydroquinazolinyl!methoxy!benzaldehyde (200 mg, 0.62 mmol) (obtained from preparation 16) and thiazolidine-2,4-dione (79 mg, 0.68 mmol) by a similar procedure to that described in example 1, mp 244°-246° C.

¹ H NMR (DMSO-d₆ +CDCl₃): δ 12.25 (bs, 1H, D₂ O exchangeable) 8.02 (d, J=7.20 Hz, 1H), 7.82-7.60 (m, 2H), 7.66 (s, 1H), 7.51 (t, J=7.20 Hz, 1H), 7.38-7.03 (m, 3H), 5.52 (s, 2H), 3.91 (s, 3H), 3.68 (s, 3H).

EXAMPLE 16 5- 4- 2- 4-Acetylamino-2-oxo-1,2-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR83##

The title compound (1.8 g, 81%) was obtained from 4- 2- 4-acetylamino-2-oxo-1,2-dihydro-1-pyrimidinyl!ethoxy!benzaldehyde (1.7 g, 5.65 mmol) (obtained from preparation 8) and thiazolidine-2,4-dione (0.661 g, 5.65 mmol) by a similar procedure to that described in example 1, mp 274° C.

¹ H NMR (CDCl₃ +DMSO-d₆): δ 12.56 (bs, 1H, D₂ O exchangeable), 10.85 (s, 1H, D₂ O exchangeable), 8.11 (d, J=7.2 Hz, 1H), 7.74 (s, 1H), 7.55 (d, J=8.30 Hz, 2H), 7.17 (d, J=7.20 Hz, 1H), 7.11 (d, J=8.30 Hz, 2H), 4.40-4.05 (m, 4H), 2.08 (s, 3H).

EXAMPLE 17 5- 4- 2- 4-methyl-2-Propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione ##STR84##

A solution of 5- 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione (5.0 g, 12.46 mmol) obtained from example 1 in 1,4-dioxane (75 ml) was reduced with hydrogen in the presence of 10% palladium on charcoal (12.0 g) at 60 psi pressure for 40 h. The mixture was filtered through a bed of celite. The filtrate was evaporated to dryness under reduced pressure, purified by column chromatography (2:1 EtOAc/petroleum ether as eluent) followed by crystallisation (CH₂ Cl₂) to afford the title compound (4.6 g, 92%), mp 144°-146° C.

¹ H NMR (CDCl₃): δ 8.25 (bs, 1H, D₂ O exchangeable) 7.12 (d, J=8.48 Hz, 2H), 6.79 (d, J=7.48 Hz, 2H), 6.21 (s, 1H), 4.47 (dd, J=9.36, 4.06 Hz, 1H), 4.41 (t, J=4.47 Hz, 2H), 4.26 (t, J=4.47 Hz, 2H), 3.41 (dd, J=14.11, 4.06 Hz, 1H), 3.10 (dd, J=14.11 9.36 Hz, 1H), 2.92 (t, J=7.63 Hz, 2H), 2.24 (s, 3H), 1.90-1.60 (m, 2H), 1.05 (t, J=7.65 Hz, 3H).

EXAMPLE 18 5- 4- 2- 2,4-Dimethyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione ##STR85##

The title compound (850 mg, 85%) was obtained from 5- 4- 2- 2,4-dimethyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione (1.0 g) (obtained from example 2) by a similar procedure to that described in example 17, mp 170° C.

¹ H NMR (CDCl₃): δ 8.15 (bs, 1H, D₂ O exchangeable), 7.14 (d, J=8.30 Hz, 2H), 6.80 (d, J=8.30, 2H), 6.21 (s, 1H), 4.50 (dd, J=9.13, 3.73 Hz, 1H), 4.48-4.20 (m, 4H), 3.41 (dd, J=14.12, 3.73 Hz, 1H), 3.13 (dd, J=14.12, 9.13 Hz, 1H), 2.70 (s, 3H), 2.25 (s, 3H).

EXAMPLE 19 5- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione ##STR86## Method A

The title compound (820 mg, 82%) was obtained from 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione (1.0 g, 2.6 mmol) (obtained from example 3) by a similar procedure to that described in example 17.

Method B

To a stirred solution of 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!-2-iminothiazolidine-4-one (1.93 g, 5.0 mmol) (obtained from preparation 26) in ethanol (15 ml) was added 2N HCl (10 ml) and refluxed for 12 h. The reaction mixture was cooled to room temperature and ethanol was removed under reduced pressure. The aqueous layer was neutralised with saturated aqueous NaCHO₃ solution and extracted with EtOAc (3×20 ml). The combined organic layer was washed with brine, dried over anhydrous Na₂ SO₄ and concentrated to yield the title compound (1.63 g, 84%) which was crystallised from CH₂ Cl₂ -pet. ether, mp 148° C. The title compound upon crystallisation from MeOH provided another polymorph, mp 155° C.

¹ H NMR (CDCl₃): δ 8.65 (bs, 1H, D₂ O exchangeable), 7.12 (d, J=8.51 Hz, 2H), 6.79 (d, J=8.51 Hz, 2H), 6.21 (s, 1H), 4.48 (dd, J=9.27, 3.83 Hz, 1H), 4.42 (t, J=4.57 Hz, 2H), 4.26 (t, J=4.57 Hz, 2H), 3.41 (dd, J=14.11, 3.83 Hz, 1H), 3.11 (dd, J=14.11, 9.27 Hz, 1H), 2.99 (q, J=7.47 Hz, 2H), 2.25 (s, 3H), 1.34 (t, J=7.47Hz, 3H).

EXAMPLE 20 5- 4- 2- 2-Butyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione ##STR87##

The title compound (780 mg, 78%) was obtained from 5- 4- 2- 2-Butyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione (1.0 g) (obtained from example 4) by a similar procedure to that described in example 17, mp 150°-152° C.

¹ H NMR (CDCl₃): δ 9.53 (bs, 1H, D₂ O exchangeable), 7.13 (d, J=8.40 Hz, 2H), 6.79 (d, J=8.40 Hz, 2H), 6.22 (s, 1H), 4.45 (dd, J=9.22, 3.83 Hz, 1H), 4.42 (t, J=4.57 Hz, 2H), 4.26 (d, J=4.57 Hz, 2H), 3.42 (dd, J=14.12 Hz, 3.83 Hz, 1H), 3.09 (dd, J=14.12, 9.22 Hz, 1H), 2.95 (t, J=7.47 Hz, 2H), 2.24 (s, 3H), 1.85-1.65 (m, 2H), 1.58-1.32 (m, 2H), 0.98 (t, J=7.38 Hz, 3H).

EXAMPLE 21 5- 4- 2- 2-Ethyl-4-phenyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione ##STR88##

The title compound (300 mg, 50%) was obtained from 5- 4- 2- 2-ethyl-4-phenyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!thiazolidine-2,4-dione (600 mg, 1.38 mmol) (obtained from example 7) by a similar procedure to that described in example 17, mp 178° C.

¹ H NMR (CDCl₃): δ 8.20-7.95 (m, 2H), 7.55-7.35 (m, 3H), 7.12 (d, J=8.30 Hz, 2H), 6.80 (d, J=8.30 Hz, 2H), 6.80 (s, 1H), 4.60-4.40 (m, 3H), 4.40-4.20 (m, 2H), 3.41 (dd, J=14.1, 3.65 Hz, 1H), 3.09 (dd and q overlap, 3H), 1.46 (t, J=7.30 Hz, 3H).

EXAMPLE 22 5- 4- 3-Methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione ##STR89## Method A

The title compound (750 mg, 75%) was obtained from 5- 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methylene!thiazolidine-2,4-dione (1.0 g) (obtained from example 12) by a similar procedure to that described in example 17.

Method B

To a stirred solution of 4- 2,4-dioxo-1,3-thiazolidine-5-yl!methyl!phenoxy!acetic acid (1.9 g, 6.75 mmol) in dichloromethane (15 ml) was added triethylamine (1.876 ml, 1.36 g, 13.48 mmol) followed by pivaloyl chloride (0.913 ml, 0.899 mg, 5.46 mmol) at 0° C. and stirring was continued for 1 h at 0° C. The above reaction mixture was added to a solution of 2-amino-N-methyl benzamide (920 mg, 6.13 mmol) in acetic acid (20 ml) and refluxed for 24 h. The reaction mixture was cooled to room temperature and acetic acid was removed under reduced pressure. To the residue water (50 ml) was added and extracted with CHCl₃ (3×25 ml). The combined CHCl₃ extracts were washed with brine, dried over anhydrous Na₂ SO₄ and concentrated to yield the title compound (2.16 g, 81%), mp 190° C.

¹ H NMR (CDCl₃): δ 8.70 (bs, 1H, D₂ O exchangeable), 8.31 (d, J=7.89 Hz, 1H), 7.88-7.68 (m, 2H), 7.60-7.45 (m, 1H), 7.19 (d, J=8.46 Hz, 2H), 7.02 (d, J=8.46 Hz, 2H), 5.18 (s, 2H), 4.50 (dd, J=9.22, 3.90 Hz, 1H), 3.75 (s, 3H), 3.45 (dd, J=14.11, 3.90 Hz, 1H), 3.13 (dd, J=14.11, 9.22 Hz, 1H).

EXAMPLE 23 5- 4- 3-Ethyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione ##STR90##

The title compound (1.186 g, 58%) was obtained from 5- 4- 3-ethyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methylene!thiazolidine-2,4-dione (2.035 g, 5.0 mmol) (obtained from example 13) by a similar procedure to that described in example 17.

¹ H NMR (CDCl₃): δ 9.20 (bs, 1H, D₂ O exchangeable) 8.30 (d, J=7.84 Hz, 1H), 7.84-7.64 (m, 2H), 7.60-7.48 (m, 1H), 7.19 (d, J=8.46 Hz, 2H), 7.02 (d, J=8.46 Hz, 2H), 5.25 (s, 2H), 4.51 (dd, J=9.30, 3.95 Hz, 1H), 3.94 (q, J=6.92 Hz, 2H), 3.42 (dd, J=14.12, 3.95 Hz, 1H), 3.11 (dd, J=14.2, 9.30 Hz, 1H), 1.35 (t, J=6.95 Hz, 3H).

EXAMPLE 24 5- 4- 2- 2-Ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione ##STR91##

The title compound (173 mg, 82%) was obtained from 5- 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!-2-iminothiazolidine-4-one (211 mg, 0.5 mmol) (obtained from preparation 27) by a similar procedure to that described in example 19 (Method B), mp 178°-180° C.

¹ H NMR (CDCl₃): δ 8.24 (d, J=7.88 Hz, 1H), 7.80-7.60 (m, 2H), 7.43 (t, J=7.56 Hz, 1H), 7.10 (d, J=8.63 Hz, 2H), 6.80 (d, J=8.63 Hz, 2H), 4.54 (t, J=5.03 Hz, 2H), 4.46 (dd, J=9.92, 3.83 Hz, 1H), 4.32 (t, J=5.03 Hz, 2H), 3.40 (dd, J=14.35, 3.83 Hz, 1H), 3.20-2.90 (m, 3H), 1.43 (t, J=7.48 Hz, 3H).

EXAMPLE 25 2- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!-1,2,4-oxadiazolidine-3,5-dione ##STR92## Method A

To a stirred solution of N- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzyl!-N-hydroxyurea (346 mg, 1.0 mmol) (obtained from preparation 19) in water (2 ml) was added 1N NaOH (3 ml) followed by ethyl chloroformate (191 μl, 217 mg, 2.0 mmol) and stirred for 1h at 30° C. The reaction mixture was diluted with water, acidified to pH 3.0 and extracted with EtOAc (3×10 ml). The combined organic layers were washed with brine, dried over anhydrous Na₂ SO₄ and concentrated to yield the title compound (283 mg, 76%).

Method B

To a cold (-5° C.) solution of 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!benzyl hydroxylamine (304 mg, 1.0 mmol) (obtained from preparation 18) in anhydrous THF (4.0 ml) was added N-(chlorocarbonyl)isocyanate (88 μl, 116 mg, 1.1 mmol) dropwise. The mixture was stirred for 30 min. and poured into 2N HCl followed by extraction with EtOAc (3×10 ml). The combined organic extracts were washed with brine, dried over anhydrous Na₂ SO₄ and concentrated to yield the title compound (264 mg, 71%).

¹ H NMR (CDCl₃ +DMSO-d₆): δ 12.40 (bs, 1H, D₂ O exchangeable), 7.25 (d, J=8.72 Hz, 2H), 6.90 (d, J=8.72 Hz, 2H), 6.15 (s, 1H), 4.70 (s, 2H), 4.40-4.25 (m, 2H), 4.25-4.12 (m, 2H), 2.91 (q, J=7.56 Hz, 2H), 2.12 (s, 3H), 1.20 (t, J=7.56 Hz, 3H).

EXAMPLE 26 5- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!oxazolidine-2,4-dione ##STR93##

To a stirred solution of 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!-2-thio-1,3-oxazolidine4-one (100 mg, 0.259 mmol) (obtained from preparation 30) in dry DMF (2 ml) was added 3-chloroperbenzoic acid (179 mg, 0.68 mmol, 65%) at 0° C. and stirred for 30 min at 0° C. to 10° C. and then at 30° C. for 5 h. The reaction mixture was diluted with ethyl acetate (10 ml), washed with water (5 ml) and then with brine (5 ml); dried over anhydrous Na₂ SO₄ and concentrated. The crude product was purified by flash chromatography to yield the title compound (72 mg, 75%).

¹ H NMR (CDCl₃ +DMSO-d₆): δ 7.6 8 (d, J=8.72 Hz, 2H), 6.91 (d, J=8.72 Hz, 2H), 6.61 (s, 1H), 6.16 (s, 1H), 4.50-4.38 (m, 2H), 4.38-4.00 (m, 2H), 3.12 (q, J=7.47 Hz, 2H), 2.24 (s, 3H), 1.35 (t, J=7.47 Hz, 3H).

EXAMPLE 27 5- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!oxazolidine-2,4-dione ##STR94## Method A

A solution of 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methylene!oxazolidine-2,4-dione (100 mg) (obtained from example 26) in 1,4-dioxane (10 ml) was reduced with hydrogen in the presence of 10% palladium on charcoal (20 mg) at 50 psi for 24 h. The mixture was filtered through a bed of celite. The filtrate was evaporated to dryness under reduced pressure, purified by column chromatography (2:1 EtOAc/petroleum ether as eluent) to afford the title compound (90 mg, 90%).

Method B

A solution of ethyl 3- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl!-2-hydroxy propionate (93 mg, 0.25 mmol) (obtained from preparation 29), urea (30 mg, 0.5 mmol) and sodium methoxide (22 mg, 0.4 mmol) in a mixture of methanol (0.5 ml) and ethanol (2.0 ml) was stirred for 2 h at 30° C., followed by reflux for 2 h. The reaction mixture was cooled to room temperature and acidified with 2N HCl to pH 4 and extracted with ethyl acetate (2×10 ml). The combined organic extracts were washed with water (5 mL), brine (5 mL), dried over anhydrous Na₂ SO₄ and concentrated to yield the title compound (35 mg, 38%).

¹ H NMR (CDCl₃ +DMSO-d₆): δ 7.14 (d, J=8.51 Hz, 2H), 6.77 (d, J=8.5 Hz, 2H), 6.17 (s, 1H), 4.95 (t, J=4.82 Hz, 1H), 4.42 (t, J=4.94 Hz, 2H), 4.24 (t, J=4.94 Hz, 2H), 3.38-3.00 (m, 2H), 3.00 (q, J=7.42 Hz, 2H), 2.25 (s, 3H), 1.34 (t, J=7.42 Hz, 3H).

EXAMPLE 28 5- 4- 3-Methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione sodium salt ##STR95##

To a stirred suspension of 5- 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione (21.0 g, 53.2 mmol) (obtained from example 22) in methanol (200 ml) was added a solution of freshly prepared sodium methoxide (11.45 g, 212 mmol) in methanol (25 ml) dropwise at 30° C. During this period the suspension slowly dissolved completely and a white solid precipitated out which was stirred further for 1h. The solid was filtered and washed with methanol (20 ml) and dried to afford the title compound (20.6 g, 93%), mp 235° C.

¹ H NMR (DMSO-d₆): δ 8.16 (d, J=7.47 Hz, 1H), 7.84 (t, J=7.47 Hz, 1H), 7.69 d, J=7.47 Hz, 1H), 7.56 (t, J=7.47 Hz, 1H), 7.15 (d, J=8.72 Hz, 2H), 7.00 (d, J=8.72 Hz, 2H), 5.25 (s, 2H), 4.09 (dd, J=10.34, 3.36 Hz, 1H), 3.61 (s, 3H), 3.30 (dd, J=13.82, 3.36 Hz, 1H), 2.62 (dd, J=13.82, 10.34 Hz, 1H).

EXAMPLE 29 5- 4- 2- 2,5,6-Trimethyl-4-oxo-3,4-dihydro-thieno- 2,3-d!-pyrimidin-3-yl!ethoxy!phenyl methylene!thiazolidine-2,4-dione ##STR96##

The title compound (550 mg, 85%) was obtained from 4- 2- 2,5,6-trimethyl-4-oxo-thieno-3-pyrimidinyl!ethoxy!benzaldehyde (500 mg, 1.46 mmol) (obtained from preparation 31) and thiazolidine-2,4-dione (257 mg, 2.2 mmol) by a similar procedure to that described in example 1, mp 280° C.

¹ H NMR (DMSO-d₆): δ 12.52 (bs, 1H, D₂ O exchangeable), 7.71 (s, 1H), 7.52 (d, J=8.38 Hz, 2H), 7.10 (d, J=8.39 Hz, 2H), 4.50-4.20 (m, 4H), 2.66 (s, 3H), 2.36 (s, 3H), 2.32 (s, 3H).

Mutation in colonies of laboratory animals and different sensitivities to dietary regimens have made the development of animal models with non-insulin dependent diabetes associated with obesity and insulin resistance possible. Genetic models such as db/db and ob/ob (See Diabetes, (1982) 31(1): 1-6) in mice and fa/fa and zucker rats have been developed by the various laboratories for understanding the pathophysiology of disease and testing the efficacy of new antidiabetic compounds (Diabetes, (1983) 32: 830-838; Annu. Rep. Sankyo Res. Lab. (1994) 46: 1-57). The homozygous animals, C57 BL/KsJ-db/db mice developed by Jackson Laboratory, U.S., are obese, hyperglycemic, hyperinsulinemic and insulin resistant (J. Clin. Invest., (1990) 85:962-967), whereas heterozygous are lean and normoglycemic. In db/db model, mouse progressively develops insulinopenia with age, a feature commonly observed in late stages of human type II diabetes when blood sugar levels are insufficiently controlled. The state of pancreas and its course vary according to the models. Since this model resembles that of type II diabetes mellitus, the compounds of the present invention were tested for blood sugar and triglycerides lowering activities.

The compounds of the present inventions showed blood sugar and triglycerides lowering activities through improved insulin resistance. This was demonstrated by the following in vivo experiments.

Male C57BL/KsJ-db/db mice of 8 to 14 weeks age, having body weight range of 35 to 60 grams, procured from the Jackson Laboratory, U.S.A., were used in the experiment. The mice were provided with standard feed (National Institute of Nutrition, Hyderabad, India) and acidified water, ad libitum. The animals having more than 300 mg/dl blood sugar were used for testing. The number of animals in each group was 4.

The random blood sugar and triglyceride levels were measured by collecting blood (100 μl) through orbital sinus, using heparinised capillary in tubes containing EDTA which was centrifuged to obtain plasma. The plasma glucose and triglycerides levels were measured through spectrometrically, by glucose oxidase and glycerol-3-PO₄ oxidase/peroxidase enzyme (Dr. Reddy's Lab. Diagnostic Division Kits, Hyderabad, India) methods respectively. On 6th day the blood samples were collected one hour after administration of test compounds/vehicle for assessing the biological activity.

Test compounds were suspended on 0.25% carboxymethyl cellulose and administered to test group at a dose of 10 mg to 100 mg/kg through oral gavage daily for 6 days. The control group received vehicle (dose 10 ml/kg). Troglitazone (100 mg/kg, daily dose) was used as a standard drug which showed 28% reduction in random blood sugar level on 6th day.

The blood sugar and triglycerides lowering activities of the test compound was calculated according to the formula:

Blood sugar/triglycerides lowering activity (%)= ##EQU1## ZC=Zero day control group value DC=Zero day treated group value

TC=Control group value on test day

DT=Treated group value on the test day

No adverse effects were observed for any of the mentioned compounds of invention in the above test.

The compounds of the present invention also showed cholesterol lowering activity in the experimental animals used.

    ______________________________________                               Maximum             Dose     Days     reduction in blood                                         Triglyceride     Compound             mg/kg/day                      treated  glucose level (%)                                         lowering (%)     ______________________________________     Example 3             100      6        67        12     Example 6             100      6        41        31     Example 7             100      6        66        35     Example 9              30      6        46        35     Example 12             100      6        71        57     Example 13             100      6        52        57     Example 17              30      6        65        45     Example 19              30      6        73        70     Example 21              30      6        64        76     Example 22              30      6        55        41     Example 24              10      6        63        17     ______________________________________

The experimental results from the db/db mice suggest that the novel compounds of the present invention also possess therapeutic utility as a prophylactic or regular treatment for obesity, cardiovascular disorders such as hypertension, hyperlipidaemia and other diseases; as it is known from the literature that such diseases are interrelated to each other. 

We claim:
 1. A compound of formula (1) ##STR97## its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates where one of the X, Y or Z represent C═O or C═S and the remaining of X, Y, and Z represent a group C═ or C═C to form a six membered ring; R¹, R² and R³ are substituents either on X, Y or Z or on a nitrogen atom and may be the same or different and represent hydrogen, halogen, hydroxy or nitro, or optionally substituted groups selected from alkyl, cycloalkyl, alkoxy, cycloalkoxy, aryl, aralkyl, heterocyclyl, heteroaryl, heteroaralkyl, acyl, acyloxy, hydroxyalkyl, amino, acylamino, arylamino, aminoalkyl, aryloxy, alkoxycarbonyl, alkylamino, alkoxyalkyl, thioalkyl, alkylthio or carboxylic acid and its derivatives or sulfonic acid and its derivatives with the provision that when R¹, R² or R³ is on a nitrogen atom its does not represent hydrogen, halogen, hydroxy, nitro; or substituted or unsubstituted aryloxy, alkoxy, cycloalkoxy, acyloxy, alkylthio, carboxy or sulfonic acid groups; or any two of R¹, R² and R³ along with the adjacent atoms to which they are attached may form a substituted or unsubstituted cyclic structure of 4 to 7 atoms with one or more double bonds which may be carbocyclic or may contain one or more heteroatoms selected from oxygen, nitrogen and sulfur; the linking group represented by--(CH₂)n-O-- may be attached either through nitrogen atom or through X, Y or Z where n is an integer ranging from 1-4; Ar represents an optionally substituted divalent aromatic or heterocyclic group; R⁴ represents hydrogen, halogen or lower alkyl group or forms a bond together with the adjacent group A; A represents a nitrogen atom or a group CR⁵ where R⁵ represents hydrogen, halogen or lower alkyl group or R⁵ forms a bond together with R⁴ ; B represents an oxygen or a sulfur atom when A is CR⁵ and B represents an oxygen when A is a nitrogen atom.
 2. A compound according to claim 1, wherein X is a C═O or C═S and Y and Z are selected from ═C and C═C.
 3. A compound according to claim 1, wherein Y is a C═O or C═S and X and Z are selected from ═C and C═C.
 4. A compound according to claim 1, wherein Z is a C═O or C═S and X and Y are selected from ═C and C═C.
 5. A compound according to claim 1, wherein R¹, R² and R³ are substituents on X, Y or Z which may be same or different and are selected from hydrogen, halogen, hydroxy, nitro, or optionally substituted groups selected from alkyl, cycloalkyl, alkoxy, cycloalkoxy, aryl, aralkyl, heterocyclyl, heteroaryl, heteroaralkyl, acyl, acyloxy, hydroxyalkyl, amino, acylamino, arylamino, aminoalkyl, aryloxy, alkoxycarbonyl, alkylamino, alkoxyalkyl, thioalkyl, alkylthio or carboxy or its derivatives or sulfonic acid or its derivatives.
 6. A compound according to claim 1, wherein one of R¹, R² or R³ is substituent on a nitrogen atom and is selected from the group consisting of substituted or unsubstituted (C₁ -C₁₂)alkyl; substituted or unsubstituted cycloalkyl; substituted or unsubstituted aryl; substituted or unsubstituted aralkyl; substituted or unsubstituted heteroaryl; substituted or unsubstituted heterocyclyl; alkoxycarbonyl; aryloxycarbonyl; amino(C_(1-C) ₆)alkyl; hydroxy(C₁ -C₆)alkyl; thio(C₁ -C₆)alkyl and acyl groups.
 7. A compound according to claim 1, wherein the cyclic structure formed by any two of R¹, R² or R³ along with the adjacent atoms to which they are attached, is substituted and the substituents are selected from the group consisting of halogen, alkyl, cycloalkyl, alkoxy, cycloalkoxy, aryl, aralkyl, heterocyclyl, heteroaryl, heteroaralkyl, hydroxy, acyl, acyloxy, hydroxyalkyl, amino, acyl, acyloxy, acylamino, aminoalkyl, aryloxy, alkoxycarbonyl, alkylamino, alkoxyalkyl, carboxylic acid or its derivatives or sulfonic acid or its derivatives.
 8. A pharmaceutical composition which comprises a compound of formula (I) ##STR98## as defined in claim 1 and pharmaceutically acceptable carriers, diluents, excipients or solvates.
 9. A pharmaceutical composition as claimed in claim 8, in the form of a tablet, capsule, powder, syrup, solution or suspension.
 10. A method of preventing or treating diseases in which insulin resistance is the underlying pathophysiological mechanism comprising administering a compound of formula (I) as defined in claim 1, and a pharmaceutically acceptable carrier, diluent or excipient to a patient in need thereof.
 11. A method according to claim 10, wherein the disease is type II diabetes, impaired glucose tolerance, dyslipidaemia, hypertension, coronary heart disease, cardiovascular disorders, atherosclerosis, insulin resistance associated with obesity and psoriasis, diabetic complications, polycystic ovarian syndrome (PCOS), renal diseases, diabetic nephropathy, glomerulonephritis, glomerular sclerosis, nephrotic syndrome, hypertensive nephrosclerosis, end-stage renal diseases, microalbuminuria, eating disorders.
 12. A compound according to claim 1 where Ar represents substituted or unsubstituted divalent phenylene, naphthylene, benzofuryl, indolinyl, azaindolyl, azaindolinyl or benzoxazolyl.
 13. A compound according to claim 1 which is selected from the group consisting of the following compounds: 5- 4- 2- 2,4-Dimethyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-butyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-ethyl-4-phenyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 3-ethyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione, 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!oxazolidine-2,4-dione, 5- 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!oxazolidine-2,4-dione, 5- 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!oxazolidine-2,4-dione, 2- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!-1,2,4-oxadiazolidine-3,5-dione, 2- 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!-1,2,4-oxadiazolidine-3,5-dione, 2- 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!-1,2,4-oxadiazolidine-3,5-dione, 5 4- 3-methyl-4-oxo-3,4-dihydro-2-quinazolinyl!methoxy!phenyl methyl!thiazolidine-2,4-dione sodium salt, 5 4- 2- 2-methyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!, thiazolidine-2,4-dione sodium salt, 5 4- 2- 2-ethyl-4-oxo-3,4-dihydro-3-quinazolinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione sodium salt, 5 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione sodium salt.
 14. A pharmaceutical composition which comprises, a compound according to claim 13 as an effective ingredient and a pharmaceutically acceptable carrier, diluent or excipient.
 15. A compound according to claim 1 which is 5- 4- 2- 2-Ethyl-4-methyl-6-oxo-1,-1dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione: ##STR99##
 16. A compound according to claim 1 which is selected from the group consisting of the following compounds: 5- 4- 2- 2,4-Dimethyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione; 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione; 5- 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione; 5- 4- 2- 2-butyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione; 5- 4- 2-ethyl-4-phenyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione; 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1pyrimidinyl!ethoxy!phenyl methyl!oxazolidine-2,4-dione; 5- 4- 2- 4-methyl-2-propyl-6-oxo -1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!oxazolidine-2,4-dione; 2- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!-1,2,4-oxadiazolidine-3,5-dione; 2- 4- 2- 4-methyl-2-propyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!-1,2,4-oxadiazolidine-3,5-dione; 5- 4- 2- 2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl!ethoxy!phenyl methyl!thiazolidine-2,4-dione sodium salt. 